nono-py 0.5.0

Python bindings for nono capability-based sandboxing

nono-py

Python bindings for nono, a capability-based sandboxing library.

nono provides OS-enforced sandboxing using Landlock (Linux) and Seatbelt (macOS). Once a sandbox is applied, unauthorized operations are structurally impossible.

Installation

pip install nono-py

From source

Requires Rust toolchain and maturin:

pip install maturin
maturin develop

Usage

from nono_py import CapabilitySet, AccessMode, apply, is_supported

# Check platform support
if not is_supported():
    print("Sandboxing not supported on this platform")
    exit(1)

# Build capability set
caps = CapabilitySet()
caps.allow_path("/tmp", AccessMode.READ_WRITE)
caps.allow_path("/home/user/project", AccessMode.READ)
caps.allow_file("/etc/hosts", AccessMode.READ)
caps.block_network()

# Apply sandbox (irreversible!)
apply(caps)

# Now the process can only access granted paths
# Network access is blocked
# This applies to all child processes too

API Reference

Enums

AccessMode

File system access mode:

• AccessMode.READ - Read-only access
• AccessMode.WRITE - Write-only access
• AccessMode.READ_WRITE - Both read and write access

Classes

CapabilitySet

A collection of capabilities that define sandbox permissions.

caps = CapabilitySet()

# Add directory access (recursive)
caps.allow_path("/tmp", AccessMode.READ_WRITE)

# Add single file access
caps.allow_file("/etc/hosts", AccessMode.READ)

# Block network
caps.block_network()

# Add platform-specific rule (macOS Seatbelt)
caps.platform_rule("(allow mach-lookup (global-name \"com.apple.system.logger\"))")

# Utility methods
caps.deduplicate()  # Remove duplicates
caps.path_covered("/tmp/foo")  # Check if path is covered
caps.fs_capabilities()  # List all fs capabilities
caps.summary()  # Human-readable summary

QueryContext

Query permissions without applying the sandbox:

caps = CapabilitySet()
caps.allow_path("/tmp", AccessMode.READ)

ctx = QueryContext(caps)

result = ctx.query_path("/tmp/file.txt", AccessMode.READ)
# {'status': 'allowed', 'reason': 'granted_path', 'granted_path': '/tmp', 'access': 'read'}

result = ctx.query_path("/var/log/test", AccessMode.READ)
# {'status': 'denied', 'reason': 'path_not_granted'}

result = ctx.query_network()
# {'status': 'allowed', 'reason': 'network_allowed'}

SandboxState

Serialize and restore capability sets:

caps = CapabilitySet()
caps.allow_path("/tmp", AccessMode.READ)

# Serialize to JSON
state = SandboxState.from_caps(caps)
json_str = state.to_json()

# Restore from JSON
restored_state = SandboxState.from_json(json_str)
restored_caps = restored_state.to_caps()

SupportInfo

Platform support information:

info = support_info()
print(info.is_supported)  # True/False
print(info.platform)      # "linux" or "macos"
print(info.details)       # Human-readable details

Policy

Load a policy.json document and resolve named groups into a CapabilitySet:

from pathlib import Path

from nono_py import CapabilitySet, load_policy

policy = load_policy(Path("examples/policy_example.json").read_text())
caps = CapabilitySet()
resolved = policy.resolve_groups(["system_tmp_read", "deny_secrets"], caps)

print(resolved.names)
print(resolved.deny_paths)
print(caps.summary())

Functions

apply(caps: CapabilitySet) -> None

Apply the sandbox. This is irreversible. Once applied, the current process and all children can only access resources granted by the capabilities.

is_supported() -> bool

Check if sandboxing is supported on this platform.

support_info() -> SupportInfo

Get detailed platform support information.

load_policy(json: str) -> Policy

Parse a policy.json document.

load_embedded_policy() -> Policy

Load the bundled nono policy shipped with the package.

Platform Support

Platform	Backend	Requirements
Linux	Landlock	Kernel 5.13+ with Landlock enabled
macOS	Seatbelt	macOS 10.5+
Windows	-	Not supported

Development

# Install dev dependencies
pip install maturin pytest mypy

# Build and install for development
make dev

# Run tests
make test

# Run linters
make lint

# Format code
make fmt

License

Apache-2.0