Pipe bindings for radare2 (r2pipe)

The r2pipe APIs are based on a single r2 primitive found behind r_core_cmd_str() which is a function that accepts a string parameter describing the r2 command to run and returns a string with the result.

The decision behind this design comes from a series of benchmarks with different libffi implementations and resulted that using the native API is more complex and slower than just using raw command strings and parsing the output.

As long as the output can be tricky to parse, it's recommended to use the JSON output and deserializing them into native language objects which results much more handy than handling and maintaining internal data structures and pointers.

Also, memory management results into a much simpler thing because you only have to care about freeing the resulting string.

Getting Started

This plugin requires radare >= 0.9.8 (some features such as lpipe require git version)

Once radare2 is installed, you may install this plugin using this command:

npm install r2pipe

Once the plugin has been installed, you can load it with this line of JavaScript:

var r2pipe = require('r2pipe');

Spawn options

The r2pipe.options array is used to specify the extra arguments passed to r2 when using any spawn method like .launch() or .pipe() and their *Sync versions.

var r2pipe = require('r2pipe');
r2pipe.options = ['-n'];
var r2 = r2pipe.open('/bin/ls');
console.log (r2.cmd('x'));
r2.quit();

Promises

In order to use promises, async, co, .. with r2pipe, checkout the r2pipe-promise module.

Access methods

There are multiple ways to interact with a radare2 session

open ([uri], [callback])

Runs different connection methods depending on the uri and the number of arguments

var r2pipe = require('r2pipe');

function doStuff (err, r2p) {
  if (!err) {
    console.log (r2p.cmdj('ij'));
  } else  {
    console.log(`Error: ${err.message}`)
  }
  r2p.quit();
}

/* rlang r2pipe script ( r2 -qi foo.js /bin/ls ) */
r2pipe.open (doStuff);

r2pipe.open ('/bin/ls', doStuff);

r2pipe.open ('http://cloud.radare.org/cmd/', doStuff);

This method can be also used when running node scripts from r2 like this:

$ cat test.js
var r2 = require('r2pipe').open();
console.log(r2.cmd('x'));
r2.quit();
$ r2 -qi test.js /bin/ls

As long as open() gets no parameters, the r2pipe api asumes you are performing a sync lpipe connection. This is the same as calling openSync().

openSync ([uri])

Runs different synchronous connection methods depending on the uri and the number of arguments

NOTE: only lang and pipe methods supported, no http or so

var r2pipe = require('r2pipe');

/* sync rlang script */
try {
  var r2p = r2pipe.openSync ();
  console.log (r2p.cmdj('ij'));
  r2p.quit();
} catch (e) {
  console.error (e.message);
}

/* sync file open */
var r2p = r2pipe.openSync ('/bin/ls');
...

pipe (binfile, callback)

Spawns a new process and comunicate with it through standard stdin, stdout, stderr file descriptors

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   ...
}

r2pipe.pipe ("/bin/ls", doSomeStuff);

lpipe (callback)

This method is intended to be used while running scripts from the r2 console

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   ...
}

r2pipe.lpipe (doSomeStuff);

Execute the script from r2 command prompt

$ r2 binfile.elf
[0x080480a0]> #!pipe node /tmp/yourscript.js
Analizing file
Analysis finished
Searching for syscalls
 - found Syscall: write
 - found Syscall: close
 - found Syscall: read
 - found Syscall: write
 - found Syscall: exit
 - found Syscall: write
 - found Syscall: munmap
 - found Syscall: mmap
[0x080480a0]>

launch (binfile, callback)

Launch radare2 and listen for cmds through a tcp port

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   ...
}

r2pipe.launch ("/bin/ls", doSomeStuff);

ioplugin(callback)

Callback for the libr/io/r2pipe plugin interface to write IO plugins using the r2pipe api.

var r2pipe = require('r2pipe');

r2pipe.ioplugin(function (err, io, msg) {
  switch (msg.op) {
    case 'read':
      var obj = {
        result: msg.count,
        data: [1, 2, 3]
      };
      io.send(obj);
      break;
    /* ... */
    default:
      io.send();
      break;
  }
});

connect (url, callback)

Connect to an already running radare2 instance running an http listener

~$ r2 -
 -- Trust no one, nor a zero. Both lie.
[0x00000000]> =h 8182
Starting http server...
open http://localhost:8182/
r2 -C http://localhost:8182/cmd/

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   ...
}

r2pipe.connect ("http://localhost:8182/cmd/", doSomeStuff);

API

r2pipes provides six basic commands

cmd (r2cmd, [callback])

Runs a radare2 command

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   r2.cmd ("iS", function(err, output) {
    console.log (output);
  });
}

r2pipe.launch ("/bin/ls", doSomeStuff);

cmdj (r2cmd, [callback])

Runs a radare2 command and tries to convert the output into an object.

Note that this will only work with commands producing JSON output.

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   r2.cmdj ("iSj", function(err, output) {
    if (output !== null)
       console.log (output);
    else
       console.log("An error has occurred");
  });
}

r2pipe.launch ("/bin/ls", doSomeStuff);

In case of error "null" will be passed as argument to the callback instead of an valid object

syscmd (oscmd, [callback])

Runs a system command, used mainly to access radare companion tools such as rabin2, raddif2, etc...

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   r2.syscmd ("rabin2 -S /bin/true", function(err, output) {
    console.log (output);
  });
}

r2pipe.launch ("/bin/ls", doSomeStuff);

syscmdj (oscmd, [callback])

Runs a system command and tries to convert the output into an object.

Note that this will only work with commands producing JSON output.

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   r2.syscmdj ("rabin2 -j -S /bin/true", function(err, output) {
    console.log (output);
  });
}
t
r2pipe.launch ("/bin/ls", doSomeStuff);

In case of error "null" will be passed as argument to the callback instead of an valid object

quit ()

Close the connection, kill the radare spawned process or terminate the lpipe script execution

var r2pipe = require('r2pipe');

function doSomeStuff(err, r2) {
   r2.quit();
}

r2pipe.launch ("/bin/ls", doSomeStuff);

Example

This is a small example using the pipe connection method for standalone scripts.

var r2pipe = require ("r2pipe");

function doSomeStuff(err, r2) {

  r2.cmdj ("aij entry0+2", function(err, o) {
    console.log (o);
  });

  r2.cmd ('af @ entry0', function(err, o) {
    r2.cmd ("pdf @ entry0", function(err, o) {
      console.log (o);
      r2.quit ()
    });
  });

}

r2pipe.pipe ("/bin/ls", doSomeStuff);
r2pipe.launch ("/bin/ls", doSomeStuff);
r2pipe.connect ("http://cloud.rada.re/cmd/", doSomeStuff);