Security and Authorization in Docker: Moby Project
Rationale for learning about this topic
Understanding the security and authorization components in Docker, including authorization, capabilities, profiles, and seccomp, is crucial for building secure and robust containerized applications. These features help ensure that containers run in a controlled environment, preventing potential security vulnerabilities and unauthorized access.
**What is Security and Authorization?
Security and Authorization in Docker refers to the mechanisms that control access to the containerized environment and the resources it uses. This includes:
- Authorization: Defining who can perform specific actions on containers and the Docker daemon.
- Capabilities: Fine-grained permissions that allow or deny specific system calls.
- Profiles: Predefined sets of capabilities that can be assigned to containers.
- Seccomp: Security Components, a feature that helps restrict system calls in containers.
**Why is Security and Authorization important?
Security and Authorization are essential for maintaining the security and integrity of containerized applications. By implementing these features, you can:
- Control access to the Docker daemon and containers.
- Limit the capabilities of containers to only the necessary system calls.
- Enforce security policies to prevent unauthorized access or actions.
- Isolate applications from each other and the host system.
Authorization
Authorization in Docker is managed using the docker-credential-helpers and docker-registry packages. These tools allow you to authenticate with registries and manage access to your containers.
Options
- Registry authentication: Authenticate with a Docker registry using a username and password or a certificate.
- Access control: Control who can access and manage containers using RBAC (Role-Based Access Control) or ACLs (Access Control Lists).
Example
To authenticate with a Docker registry, you can use the docker login command:
$ docker login myregistry.com --username myusername --password mypassword
For more information, refer to the Docker documentation on authentication.
Capabilities
Capabilities are a fine-grained way to control the permissions of a container. They allow or deny specific system calls based on their security level.
Options
- Enable/disable capabilities: You can enable or disable capabilities for a container using the
--cap-addand--cap-dropflags when running a container. - List capabilities: You can list the capabilities of a container using the
docker inspectcommand.
Example
To run a container with the NET_ADMIN capability, use the following command:
$ docker run --cap-add=NET_ADMIN myimage:latest
For more information, refer to the Docker documentation on capabilities.
Profiles
Profiles are predefined sets of capabilities that can be assigned to containers. They help simplify the process of managing container permissions.
Options
- Create a profile: You can create a custom profile using the
docker createcommand and the--privilegedflag. - Assign a profile to a container: You can assign a profile to a container using the
--security-optflag when running a container.
Example
To create a custom profile named myprofile and assign it to a container, use the following commands:
# Create a custom profile
$ docker create --name myprofile --privileged myimage:latest
# Assign the profile to a container
$ docker run --security-opt seccomp=/path/to/myprofile myimage:latest
For more information, refer to the Docker documentation on profiles.
Seccomp
Seccomp (Security Components) is a feature that helps restrict system calls in containers. It allows you to define a whitelist or blacklist of system calls that can be used by the container.
Options
- Create a seccomp profile: You can create a custom seccomp profile using a JSON file or a predefined template.
- Assign a seccomp profile to a container: You can assign a seccomp profile to a container using the
--security-optflag when running a container.
Example
To create a custom seccomp profile named myseccomp.json and assign it to a container, use the following commands:
# Create a custom seccomp profile
$ cat > myseccomp.json << EOF
{
"seccomp": {
"profile": {
"defaultAction": "deny",
"rules": [
{
"action": "allow",
"arch": ["x86_64"],
"syscall": ["sysctl", "getpriority"]
}
]
}
}
}
EOF
# Assign the seccomp profile to a container
$ docker run --security-opt seccomp=/path/to/myseccomp.json myimage:latest
For more information, refer to the Docker documentation on seccomp.
