ef1614edb2
Fixes: #7573
To enable this feature, build your rootfs using AGENT_POLICY=yes. The
default is AGENT_POLICY=no.
Building rootfs using AGENT_POLICY=yes has the following effects:
1. The kata-opa service gets included in the Guest image.
2. The agent gets built using AGENT_POLICY=yes.
After this patch, the shim calls SetPolicy if and only if a Policy
annotation is attached to the sandbox/pod. When creating a sandbox/pod
that doesn't have an attached Policy annotation:
1. If the agent was built using AGENT_POLICY=yes, the new sandbox uses
the default agent settings, that might include a default Policy too.
2. If the agent was built using AGENT_POLICY=no, the new sandbox is
executed the same way as before this patch.
Any SetPolicy calls from the shim to the agent fail if the agent was
built using AGENT_POLICY=no.
If the agent was built using AGENT_POLICY=yes:
1. The agent reads the contents of a default policy file during sandbox
start-up.
2. The agent then connects to the OPA service on localhost and sends
the default policy to OPA.
3. If the shim calls SetPolicy:
a. The agent checks if SetPolicy is allowed by the current
policy (the current policy is typically the default policy
mentioned above).
b. If SetPolicy is allowed, the agent deletes the current policy
from OPA and replaces it with the new policy it received from
the shim.
A typical new policy from the shim doesn't allow any future SetPolicy
calls.
4. For every agent rpc API call, the agent asks OPA if that call
should be allowed. OPA allows or not a call based on the current
policy, the name of the agent API, and the API call's inputs. The
agent rejects any calls that are rejected by OPA.
When building using AGENT_POLICY_DEBUG=yes, additional Policy logging
gets enabled in the agent. In particular, information about the inputs
for agent rpc API calls is logged in /tmp/policy.txt, on the Guest VM.
These inputs can be useful for investigating API calls that might have
been rejected by the Policy. Examples:
1. Load a failing policy file test1.rego on a different machine:
opa run --server --addr 127.0.0.1:8181 test1.rego
2. Collect the API inputs from Guest's /tmp/policy.txt and test on the
machine where the failing policy has been loaded:
curl -X POST http://localhost:8181/v1/data/agent_policy/CreateContainerRequest \
--data-binary @test1-inputs.json
Signed-off-by: Dan Mihai <dmihai@microsoft.com>
(cherry picked from commit ab829d1038)
Note: this is cherrypicked to help with the following:
- Provide a building block to continue experimenting with policy and identify issues at the earliest.
This is especially helpful for remote hypervisor (peer-pods) as currently we have no way to test
this feature and identify areas of improvements as part of merge to main.
- Provide a building building block to prototype and understand any potential gaps or integration
issues with the initdata specification discussed in the following issue - https://github.com/confidential-containers/confidential-containers/issues/171
There are no tests for this feature in CCv0 branch and you should use it at your own risk.
Signed-off-by: Pradipta Banerjee <pradipta.banerjee@gmail.com>
Kata Containers
Welcome to Kata Containers!
This repository is the home of the Kata Containers code for the 2.0 and newer releases.
If you want to learn about Kata Containers, visit the main Kata Containers website.
Introduction
Kata Containers is an open source project and community working to build a standard implementation of lightweight Virtual Machines (VMs) that feel and perform like containers, but provide the workload isolation and security advantages of VMs.
License
The code is licensed under the Apache 2.0 license. See the license file for further details.
Platform support
Kata Containers currently runs on 64-bit systems supporting the following technologies:
| Architecture | Virtualization technology |
|---|---|
x86_64, amd64 |
Intel VT-x, AMD SVM |
aarch64 ("arm64") |
ARM Hyp |
ppc64le |
IBM Power |
s390x |
IBM Z & LinuxONE SIE |
Hardware requirements
The Kata Containers runtime provides a command to determine if your host system is capable of running and creating a Kata Container:
$ kata-runtime check
Notes:
This command runs a number of checks including connecting to the network to determine if a newer release of Kata Containers is available on GitHub. If you do not wish this to check to run, add the
--no-network-checksoption.By default, only a brief success / failure message is printed. If more details are needed, the
--verboseflag can be used to display the list of all the checks performed.If the command is run as the
rootuser additional checks are run (including checking if another incompatible hypervisor is running). When running asroot, network checks are automatically disabled.
Getting started
See the installation documentation.
Documentation
See the official documentation including:
Configuration
Kata Containers uses a single configuration file which contains a number of sections for various parts of the Kata Containers system including the runtime, the agent and the hypervisor.
Hypervisors
See the hypervisors document and the Hypervisor specific configuration details.
Community
To learn more about the project, its community and governance, see the community repository. This is the first place to go if you wish to contribute to the project.
Getting help
See the community section for ways to contact us.
Raising issues
Please raise an issue in this repository.
Note: If you are reporting a security issue, please follow the vulnerability reporting process
Developers
See the developer guide.
Components
Main components
The table below lists the core parts of the project:
| Component | Type | Description |
|---|---|---|
| runtime | core | Main component run by a container manager and providing a containerd shimv2 runtime implementation. |
| runtime-rs | core | The Rust version runtime. |
| agent | core | Management process running inside the virtual machine / POD that sets up the container environment. |
dragonball |
core | An optional built-in VMM brings out-of-the-box Kata Containers experience with optimizations on container workloads |
| documentation | documentation | Documentation common to all components (such as design and install documentation). |
| tests | tests | Excludes unit tests which live with the main code. |
Additional components
The table below lists the remaining parts of the project:
| Component | Type | Description |
|---|---|---|
| packaging | infrastructure | Scripts and metadata for producing packaged binaries (components, hypervisors, kernel and rootfs). |
| kernel | kernel | Linux kernel used by the hypervisor to boot the guest image. Patches are stored here. |
| osbuilder | infrastructure | Tool to create "mini O/S" rootfs and initrd images and kernel for the hypervisor. |
| kata-debug | infrastructure | Utility tool to gather Kata Containers debug information from Kubernetes clusters. |
agent-ctl |
utility | Tool that provides low-level access for testing the agent. |
kata-ctl |
utility | Tool that provides advanced commands and debug facilities. |
log-parser-rs |
utility | Tool that aid in analyzing logs from the kata runtime. |
trace-forwarder |
utility | Agent tracing helper. |
runk |
utility | Standard OCI container runtime based on the agent. |
ci |
CI | Continuous Integration configuration files and scripts. |
katacontainers.io |
Source for the katacontainers.io site. |
Packaging and releases
Kata Containers is now available natively for most distributions.
Metrics tests
See the metrics documentation.
Glossary of Terms
See the glossary of terms related to Kata Containers.