Recog is a framework for identifying products, services, operating systems, and hardware by matching fingerprints against data returned from various network probes. Recog makes it simple to extract useful information from web server banners, snmp system description fields, and a whole lot more.
Recog is open source, please see the LICENSE file for more information.
Recog consists of both XML fingerprint files and an assortment of code, mostly in Ruby, that makes it easy to develop, test, and use the contained fingerprints. In order to use the included ruby code, a recent version of Ruby (2.31+) is required, along with Rubygems and the bundler
gem. Once these dependencies are in place, use the following commands to grab the latest source code and install any additional dependencies.
$ git clone git@github.com:rapid7/recog.git
$ cd recog
$ bundle install
Please note that while the XML fingerprints themselves are quite stable and well-tested, the Ruby codebase in Recog is still fairly new and subject to change quickly. Please contact us (research[at]rapid7.com) before leveraging the Recog code within any production projects.
The fingerprints within Recog are stored in XML files, each of which is designed to match a specific protocol response string or field. For example, the file ssh_banners.xml can determine the os, vendor, and sometimes hardware product by matching the initial SSH daemon banner string.
A fingerprint file consists of an XML document like the following:
<fingerprints matches="ssh.banner">
<fingerprint pattern="^RomSShell_([\d\.]+)$">
<description>Allegro RomSShell SSH</description>
<example service.version="4.62">RomSShell_4.62</example>
<param pos="0" name="service.vendor" value="Allegro"/>
<param pos="0" name="service.product" value="RomSShell"/>
<param pos="1" name="service.version"/>
</fingerprint>
</fingerprints>
The first line should always consist of the XML version declaration. The first element should always be a fingerprints
block with a matches
attribute indicating what data this fingerprint file is supposed to match. The matches
attribute is normally in the form of protocol.field
.
Inside of the fingerprints
element there should be one or more fingerprint
elements. Every fingerprint
must contain a pattern
attribute, which contains the regular expression to be used to match against the data. An optional flags
attribute can be specified to control how the regular expression is to be interpreted. See the Recog documentation for FLAG_MAP
for more information.
Inside of the fingerprint, a description
element should contain a human-readable string describing this fingerprint.
At least one example
element should be present, however multiple example
elements are preferred. These elements are used as part of the test coverage present in rspec
which validates that the provided data matches the specified regular expression. Additionally, if the fingerprint is using the param
elements to extract field values from the data (described next), you can add these expected extractions as attributes for the example
elements. In the example above, this:
<example service.version="4.62">RomSShell_4.62</example>
tests that RomSShell_4.62
matches the provided regular expression and that the value of service.version
is 4.62.
The param
elements contain a pos
attribute, which indicates what capture field from the pattern
should be extracted, or 0
for a static string. The name
attribute is the key that will be reported in the case of a successful match and the value
will either be a static string for pos
values of 0
or missing and taken from the captured field.
The example
string can be base64 encoded to permit the use of unprintable characters. To signal this to Recog an _encoding
attribute with the value of base64
is added to the example
element. Based64 encoded text that is longer than 80 characters may be wrapped with newlines as shown below to aid in readability.
<example _encoding="base64">
dGllczGEAAAAlQQWMS4yLjg0MC4xMTM1NTYuMS40LjgwMAQuZGF0YS5yZW1vdmVkLjCEAAAAK
AQdZG9tYWluQ29udHJvbGxlckZ1bmN0aW9uYWxpdHkxhAAAAAMEATc=
</example>
Additionally, examples can be placed in a directory with the same base name as the XML file, in the same directory as the XML file:
xml/services.xml
xml/services/file1
xml/services/file2
...
They can then be loaded using the _filename
attribute:
<example _filename="file1"/>
This is useful for long examples.
The users and maintainers of Recog would greatly appreciate any contributions you can make to the project. For guidelines and instructions please see CONTRIBUTING.MD