The Official Radare2 Book

SDB stands for String DataBase. It's a simple key-value database that only operates with strings created by pancake. It is used in many parts of r2 to have a disk and in-memory database which is small and fast to manage using it as a hashtable on steroids.

SDB is a simple string key/value database based on djb’s cdb disk storage and supports JSON and arrays introspection.

There’s also the sdbtypes: a vala library that implements several data structures on top of an sdb or a memcache instance.

SDB supports:

• namespaces (multiple sdb paths)

• atomic database sync (never corrupted)

• bindings for vala, luvit, newlisp and nodejs

• commandline frontend for sdb databases

• memcache client and server with sdb backend

• arrays support (syntax sugar)

• json parser/getter

Usage example

Let's create a database!

$ sdb d hello=world

$ sdb d hello

world

Using arrays:

$ sdb - '[]list=1,2' '[0]list' '[0]list=foo' '[]list' '[+1]list=bar'

1

foo

2

foo

bar

2

Let's play with json:

$ sdb d g='{"foo":1,"bar":{"cow":3}}'

$ sdb d g?bar.cow

3

$ sdb - user='{"id":123}' user?id=99 user?id

99

Using the command line without any disk database:

$ sdb - foo=bar foo a=3 +a -a

bar

4

3

$ sdb -

foo=bar

foo

bar

a=3

+a

4

-a

3

Remove the database

$ rm -f d

So what ?

So, you can now do this inside your radare2 sessions!

Let's take a simple binary, and check what is already sdbized.

$ cat test.c

int main(){

puts("Hello world\n");

}

$ gcc test.c -o test

$ r2 -A ./test

[0x08048320]> k **

bin

anal

syscall

debug

[0x08048320]> k bin/**

fd.6

[0x08048320]> k bin/fd.6/*

archs=0:0:x86:32

The file corresponding to the sixth file descriptor is a x86_32 binary.

[0x08048320]> k anal/meta/*

meta.s.0x80484d0=12,SGVsbG8gd29ybGQ=

[...]

[0x08048320]> ?b64- SGVsbG8gd29ybGQ=

Hello world

Strings are stored encoded in base64.

More Examples

List namespaces

k **

List sub-namespaces

k anal/**

List keys

k *

k anal/*

Set a key

k foo=bar

Get the value of a key

k foo

List all syscalls

k syscall/*~^0x

List all comments

k anal/meta/*~.C.

Show a comment at given offset:

k %anal/meta/[1]meta.C.0x100005000