SDB

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