Cloud Native Runtime Security
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Mark Stemm 1f28f85bdf
K8s audit evts (#450)
* Add new json/webserver libs, embedded webserver

Add two new external libraries:

 - nlohmann-json is a better json library that has stronger use of c++
   features like type deduction, better conversion from stl structures,
   etc. We'll use it to hold generic json objects instead of jsoncpp.

 - civetweb is an embeddable webserver that will allow us to accept
   posted json data.

New files webserver.{cpp,h} start an embedded webserver that listens for
POSTS on a configurable url and passes the json data to the falco
engine.

New falco config items are under webserver:
  - enabled: true|false. Whether to start the embedded webserver or not.
  - listen_port. Port that webserver listens on
  - k8s_audit_endpoint: uri on which to accept POSTed k8s audit events.

(This commit doesn't compile entirely on its own, but we're grouping
these related changes into one commit for clarity).

* Don't use relative paths to find lua code

You can look directly below PROJECT_SOURCE_DIR.

* Reorganize compiler lua code

The lua compiler code is generic enough to work on more than just
sinsp-based rules, so move the parts of the compiler related to event
types and filterchecks out into a standalone lua file
sinsp_rule_utils.lua.

The checks for event types/filterchecks are now done from rule_loader,
and are dependent on a "source" attribute of the rule being
"sinsp". We'll be adding additional types of events next that come from
sources other than system calls.

* Manage separate syscall/k8s audit rulesets

Add the ability to manage separate sets of rules (syscall and
k8s_audit). Stop using the sinsp_evttype_filter object from the sysdig
repo, replacing it with falco_ruleset/falco_sinsp_ruleset from
ruleset.{cpp,h}. It has the same methods to add rules, associate them
with rulesets, and (for syscall) quickly find the relevant rules for a
given syscall/event type.

At the falco engine level, there are new parallel interfaces for both
types of rules (syscall and k8s_audit) to:
  - add a rule: add_k8s_audit_filter/add_sinsp_filter
  - match an event against rules, possibly returning a result:
    process_sinsp_event/process_k8s_audit_event

At the rule loading level, the mechanics of creating filterchecks
objects is handled two factories (sinsp_filter_factory and
json_event_filter_factory), both of which are held by the engine.

* Handle multiple rule types when parsing rules

Modify the steps of parsing a rule's filter expression to handle
multiple types of rules. Notable changes:

 - In the rule loader/ast traversal, pass a filter api object down,
   which is passed back up in the lua parser api calls like nest(),
   bool_op(), rel_expr(), etc.
 - The filter api object is either the sinsp factory or k8s audit
   factory, depending on the rule type.
 - When the rule is complete, the complete filter is passed to the
   engine using either add_sinsp_filter()/add_k8s_audit_filter().

* Add multiple output formatting types

Add support for multiple output formatters. Notable changes:

 - The falco engine is passed along to falco_formats to gain access to
   the engine's factories.
 - When creating a formatter, the source of the rule is passed along
   with the format string, which controls which kind of output formatter
   is created.

Also clean up exception handling a bit so all lua callbacks catch all
exceptions and convert them into lua errors.

* Add support for json, k8s audit filter fields

With some corresponding changes in sysdig, you can now create general
purpose filter fields and events, which can be tied together with
nesting, expressions, and relational operators. The classes here
represent an instance of these fields devoted to generic json objects as
well as k8s audit events. Notable changes:

 - json_event: holds a json object, used by all of the below

 - json_event_filter_check: Has the ability to extract values out of a
   json_event object and has the ability to define macros that associate
   a field like "group.field" with a json pointer expression that
   extracts a single property's value out of the json object. The basic
   field definition also allows creating an index
   e.g. group.field[index], where a std::function is responsible for
   performing the indexing. This class has virtual void methods so it
   must be overridden.

 - jevt_filter_check: subclass of json_event_filter_check and defines
   the following fields:
     - jevt.time/jevt.rawtime: extracts the time from the underlying json object.
     - jevt.value[<json pointer>]: general purpose way to extract any
       json value out of the underlying object. <json pointer> is a json
       pointer expression
     - jevt.obj: Return the entire object, stringified.

 - k8s_audit_filter_check: implements fields that extract values from
   k8s audit events. Most of the implementation is in the form of macros
   like ka.user.name, ka.uri, ka.target.name, etc. that just use json
   pointers to extact the appropriate value from a k8s audit event. More
   advanced fields like ka.uri.param, ka.req.container.image use
   indexing to extract individual values out of maps or arrays.

 - json_event_filter_factory: used by things like the lua parser api,
   output formatter, etc to create the necessary objects and return
   them.

  - json_event_formatter: given a format string, create the necessary
    fields that will be used to create a resolved string when given a
    json_event object.

* Add ability to list fields

Similar to sysdig's -l option, add --list (<source>) to list the fields
supported by falco. With no source specified, will print all
fields. Source can be "syscall" for inspector fields e.g. what is
supported by sysdig, or "k8s_audit" to list fields supported only by the
k8s audit support in falco.

* Initial set of k8s audit rules

Add an initial set of k8s audit rules. They're broken into 3 classes of
rules:

 - Suspicious activity: this includes things like:
    - A disallowed k8s user performing an operation
    - A disallowed container being used in a pod.
    - A pod created with a privileged pod.
    - A pod created with a sensitive mount.
    - A pod using host networking
    - Creating a NodePort Service
    - A configmap containing private credentials
    - A request being made by an unauthenticated user.
    - Attach/exec to a pod. (We eventually want to also do privileged
      pods, but that will require some state management that we don't
      currently have).
    - Creating a new namespace outside of an allowed set
    - Creating a pod in either of the kube-system/kube-public namespaces
    - Creating a serviceaccount in either of the kube-system/kube-public
      namespaces
    - Modifying any role starting with "system:"
    - Creating a clusterrolebinding to the cluster-admin role
    - Creating a role that wildcards verbs or resources
    - Creating a role with writable permissions/pod exec permissions.
 - Resource tracking. This includes noting when a deployment, service,
    - configmap, cluster role, service account, etc are created or destroyed.
 - Audit tracking: This tracks all audit events.

To support these rules, add macros/new indexing functions as needed to
support the required fields and ways to index the results.

* Add ability to read trace files of k8s audit evts

Expand the use of the -e flag to cover both .scap files containing
system calls as well as jsonl files containing k8s audit events:

If a trace file is specified, first try to read it using the
inspector. If that throws an exception, try to read the first line as
json. If both fail, return an error.

Based on the results of the open, the main loop either calls
do_inspect(), looping over system events, or
read_k8s_audit_trace_file(), reading each line as json and passing it to
the engine and outputs.

* Example showing how to enable k8s audit logs.

An example of how to enable k8s audit logging for minikube.

* Add unit tests for k8s audit support

Initial unit test support for k8s audit events. A new multiplex file
falco_k8s_audit_tests.yaml defines the tests. Traces (jsonl files) are
in trace_files/k8s_audit and new rules files are in
test/rules/k8s_audit.

Current test cases include:

- User outside allowed set
- Creating disallowed pod.
- Creating a pod explicitly on the allowed list
- Creating a pod w/ a privileged container (or second container), or a
  pod with no privileged container.
- Creating a pod w/ a sensitive mount container (or second container), or a
  pod with no sensitive mount.
- Cases for a trace w/o the relevant property + the container being
  trusted, and hostnetwork tests.
- Tests that create a Service w/ and w/o a NodePort type.
- Tests for configmaps: tries each disallowed string, ensuring each is
  detected, and the other has a configmap with no disallowed string,
  ensuring it is not detected.
- The anonymous user creating a namespace.
- Tests for all kactivity rules e.g. those that create/delete
  resources as compared to suspicious activity.
- Exec/Attach to Pod
- Creating a namespace outside of an allowed set
- Creating a pod/serviceaccount in kube-system/kube-public namespaces
- Deleting/modifying a system cluster role
- Creating a binding to the cluster-admin role
- Creating a cluster role binding that wildcards verbs or resources
- Creating a cluster role with write/pod exec privileges

* Don't manually install gcc 4.8

gcc 4.8 should already be installed by default on the vm we use for
travis.
2018-11-09 10:15:39 -08:00
cla adding govt CLA 2017-08-04 13:59:17 -07:00
cpack/debian Add ability to read rules files from directories (#348) 2018-04-05 17:03:37 -07:00
docker Add netcat to docker images (#456) 2018-11-05 17:50:53 -08:00
examples K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
integrations Port Kubernetes Response Engine to AWS Technology (#460) 2018-11-07 08:34:13 -08:00
rules K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
scripts Load/unload kernel module on start/stop (#459) 2018-11-06 13:07:50 -08:00
test K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
userspace K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
.gitignore Add *.pyc to .gitignore 2017-06-14 13:04:14 -07:00
.travis.yml K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
CHANGELOG.md Prepare for 0.12.1 (#417) 2018-09-11 13:33:14 -07:00
CMakeCPackOptions.cmake Better copyright notices (#426) 2018-09-26 19:49:19 -07:00
CMakeLists.txt K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
CODE_OF_CONDUCT Clean up Readme, Add CNCF requested files for project. (#440) 2018-10-10 01:50:17 -05:00
COPYING Change license to Apache 2.0 (#419) 2018-09-20 11:47:10 -07:00
falco.yaml K8s audit evts (#450) 2018-11-09 10:15:39 -08:00
GOVERNANCE Clean up Readme, Add CNCF requested files for project. (#440) 2018-10-10 01:50:17 -05:00
MAINTAINERS Clean up Readme, Add CNCF requested files for project. (#440) 2018-10-10 01:50:17 -05:00
README.md Update repo links. (#447) 2018-11-07 08:35:10 -08:00

Falco

Latest release

v0.12.1 Read the change log

Dev Branch: Build Status
Master Branch: Build Status

Overview

Falco is a behavioral activity monitor designed to detect anomalous activity in your applications. Powered by sysdigs system call capture infrastructure, Falco lets you continuously monitor and detect container, application, host, and network activity... all in one place, from one source of data, with one set of rules.

Falco is hosted by the Cloud Native Computing Foundation (CNCF) as a sandbox level project. If you are an organization that wants to help shape the evolution of technologies that are container-packaged, dynamically-scheduled and microservices-oriented, consider joining the CNCF. For details read the Falco CNCF project proposal.

What kind of behaviors can Falco detect?

Falco can detect and alert on any behavior that involves making Linux system calls. Falco alerts can be triggered by the use of specific system calls, their arguments, and by properties of the calling process. For example, you can easily detect things like:

  • A shell is run inside a container
  • A container is running in privileged mode, or is mounting a sensitive path like /proc from the host.
  • A server process spawns a child process of an unexpected type
  • Unexpected read of a sensitive file (like /etc/shadow)
  • A non-device file is written to /dev
  • A standard system binary (like ls) makes an outbound network connection

How Falco Compares to Other Security Tools like SELinux, Auditd, etc.

One of the questions we often get when we talk about Falco is “How does it compare to other tools like SELinux, AppArmor, Auditd, etc. that also have security policies?”. We wrote a blog post comparing Falco to other tools.

Documentation

Visit the wiki for full documentation on falco.

Join the Community

  • Website for Falco.
  • We are working on a blog for the Falco project. In the meantime you can find Falco posts over on the Sysdig blog.
  • Join our Public Slack channel for open source sysdig and Falco announcements and discussions.

License Terms

Falco is licensed to you under the Apache 2.0 open source license.

Contributor License Agreements

Background

We are formalizing the way that we accept contributions of code from the contributing community. We must now ask that contributions to falco be provided subject to the terms and conditions of a Contributor License Agreement (CLA). The CLA comes in two forms, applicable to contributions by individuals, or by legal entities such as corporations and their employees. We recognize that entering into a CLA with us involves real consideration on your part, and weve tried to make this process as clear and simple as possible.

Weve modeled our CLA off of industry standards, such as the CLA used by Kubernetes. Note that this agreement is not a transfer of copyright ownership, this simply is a license agreement for contributions, intended to clarify the intellectual property license granted with contributions from any person or entity. It is for your protection as a contributor as well as the protection of falco; it does not change your rights to use your own contributions for any other purpose.

For some background on why contributor license agreements are necessary, you can read FAQs from many other open source projects:

As always, we are grateful for your past and present contributions to falco.

What do I need to do in order to contribute code?

Individual contributions: Individuals who wish to make contributions must review the Individual Contributor License Agreement and indicate agreement by adding the following line to every GIT commit message:

falco-CLA-1.0-signed-off-by: Joe Smith <joe.smith@email.com>

Use your real name; pseudonyms or anonymous contributions are not allowed.

Corporate contributions: Employees of corporations, members of LLCs or LLPs, or others acting on behalf of a contributing entity, must review the Corporate Contributor License Agreement, must be an authorized representative of the contributing entity, and indicate agreement to it on behalf of the contributing entity by adding the following lines to every GIT commit message:

falco-CLA-1.0-contributing-entity: Full Legal Name of Entity
falco-CLA-1.0-signed-off-by: Joe Smith <joe.smith@email.com>

Use a real name of a natural person who is an authorized representative of the contributing entity; pseudonyms or anonymous contributions are not allowed.

Government contributions: Employees or officers of the United States Government, must review the Government Contributor License Agreement, must be an authorized representative of the contributing entity, and indicate agreement to it on behalf of the contributing entity by adding the following lines to every GIT commit message:

falco-CLA-1.0-contributing-govt-entity: Full Legal Name of Entity
falco-CLA-1.0-signed-off-by: Joe Smith <joe.smith@email.com>
This file is a work of authorship of an employee or officer of the United States Government and is not subject to copyright in the United States under 17 USC 105.

Use a real name of a natural person who is an authorized representative of the contributing entity; pseudonyms or anonymous contributions are not allowed.