Radare2 has its own format of the signatures, allowing to both load/apply and create them on the fly. They are available under the z command namespace:
[0x000100b0]> z?
|Usage: z[*j-aof/cs] [args] # Manage zignatures
| z show zignatures
| z* show zignatures in radare format
| zj show zignatures in json format
| z-zignature delete zignature
| z-* delete all zignatures
| za[?] add zignature
| zo[?] manage zignature files
| zf[?] manage FLIRT signatures
| z/[?] search zignatures
| zc check zignatures at address
| zs[?] manage zignspaces
To load the created signature file you need to load it from SDB file using zo command or from the compressed SDB file using zoz command.
To create signature you need to make function first, then you can create it from the function:
r2 /bin/ls
[0x000051c0]> aaa # this creates functions, including 'entry0'
[0x000051c0]> zaf entry0 entry
[0x000051c0]> z
entry:
bytes: 31ed4989d15e4889e24883e4f050544c............48............48............ff..........f4
graph: cc=1 nbbs=1 edges=0 ebbs=1
offset: 0x000051c0
[0x000051c0]>
As you can see it made a new signature with a name entry from a function entry0. You can show it in JSON format too, which can be useful for scripting:
To remove it just run z-entry But if you want to save all created signatures, you need to save it into the SDB file using command zos myentry. Then we can apply them. Lets open a file again:
r2 /bin/ls
-- Log On. Hack In. Go Anywhere. Get Everything.
[0x000051c0]> zo myentry
[0x000051c0]> z
entry:
bytes: 31ed4989d15e4889e24883e4f050544c............48............48............ff..........f4
graph: cc=1 nbbs=1 edges=0 ebbs=1
offset: 0x000051c0
[0x000051c0]>
This means that the signatures were successfully loaded from the file myentry and now we can search matching functions:
Note that zc command just checks the signatures against the current address. To search signatures across the all file we need to do a bit different thing. There is an important moment though, if we just run it "as is" - it wont find anything:
[0x000051c0]> e search.in=io.section
[0x000051c0]> z/
[+] searching 0x000038b0 - 0x00015898
[+] searching function metrics
hits: 1
[0x000051c0]>
We are setting the search mode to io.section (it was file by default) to search in the current section (assuming we are currently in the .text section of course). Now we can check, what radare2 found for us:
Here we can see the comment of entry0, which is taken from the ELF parsing, but also the sign.bytes.entry_0, which is exactly the result of matching signature.
Signatures configuration stored in the zign. config vars' namespace:
