macOS
Homebrewverified · 100%
brew install onioncatlocal Homebrew formula metadata
MacPortsverified · 94%
sudo port install onioncatMacPorts ports tree · net/onioncat/Portfile · source: api.github.com
brew
Install onioncat with Homebrew, apk, MacPorts, zypper, scoop, winget
VPN-adapter that provides location privacy using Tor or I2P. Version 4.11.0 via Homebrew; verified from local package data.
install
Additional install commands
Linux
Alpine Linux apkverified · 92%
sudo apk add onioncatAlpine Linux edge package indexes · onioncat · source: dl-cdn.alpinelinux.org
openSUSE zypperverified · 92%
sudo zypper install onioncatopenSUSE Tumbleweed package metadata · onioncat · source: download.opensuse.org
Windows
Scoopverified · 92%
scoop install extras/ocatScoop official bucket manifest trees · bucket/ocat.json · source: api.github.com
Windows Package Managerverified · 92%
winget install --id ic005k.OCAuxiliaryTools -eWindows Package Manager source index · ic005k.OCAuxiliaryTools · source: cdn.winget.microsoft.com
overview
Package summary
VPN-adapter that provides location privacy using Tor or I2P
Project links
Commands and aliases
- ocat
history
Project history and usage
OnionCat is a long-running networking experiment that maps Tor hidden services or I2P tunnels into an IPv6 TUN interface. It makes onion/I2P endpoints look like peers on an IP network, so ordinary IP-based protocols can travel over Tor or I2P hidden-service transports.
Project history
OnionCat development began in 2008, when Tor hidden-service v2 identifiers were short enough to be reversibly mapped into IPv6 addresses under a special prefix. Its own documentation describes the core trick as translating between OnionCat IPv6 addresses and .onion hostnames, then forwarding packets between a local TUN device and remote OnionCat peers.
The move from Tor v2 hidden services to v3 onion services challenged OnionCat's original design because v3 identifiers no longer fit inside an IPv6 address. OnionCat4 added lookup machinery to preserve the virtual-network model after the identifier-size change.
Adoption history
OnionCat has been packaged beyond a single ecosystem: Debian documented an ocat(1) man page by the Jessie era, and Homebrew packages onioncat for macOS and Linux users. Its GitHub repository is the official upstream and had an onioncat-4.11.0 release dated March 9, 2023.
How it is used
Users run ocat with a local onion or I2P identifier, and OnionCat opens a TUN device, assigns it a derived IPv6 address, and relays packets through Tor or I2P. The tool can carry TCP, UDP, and other IP-based traffic, making it resemble a peer-to-peer VPN between hidden services rather than a web-only Tor client.
The README also exposes OnionCat's operational rough edges: it is a userland connector, depends on Tor/I2P setup, and does not add its own encryption on top of the transport. That makes it a tool for operators who understand the underlying anonymity network rather than a general-purpose consumer VPN.
Why package nerds care
OnionCat matters because it is one of the more literal attempts to package 'IP over onion services' as a Unix-style command. It combines old-school TUN-device networking, IPv6 address mapping, Tor/I2P naming, and distro packaging into a compact but unusual formula.
Timeline
- 2008: OnionCat development began around Tor hidden-service v2 identifiers.
- 2015: Debian Jessie shipped an onioncat man page documenting ocat as an IP-transparent Tor/I2P connector.
- 2023-03-09: onioncat-4.11.0 was published as a GitHub release.
- 2023-10-25: the upstream README/man-page text identified ocat and documented OnionCat4 behavior.
Related projects
- Related projects and technologies include Tor onion services, I2P server tunnels, TUN/TAP virtual network interfaces, and VPN-style tunneling tools.
Sources
security posture
Risk level: green
narrow executable package without higher-risk signals.
Risk classifier
green risk · low confidence · appliance
Why
- narrow executable package without higher-risk signals
Signals
- metadata:no-higher-risk-signals
Install behavior
- No Homebrew post-install hook is recorded in formula metadata.
- Homebrew bottle metadata is available for 12 platform targets.
- Installs with 1 runtime dependencies.
- Build metadata lists 2 build dependencies.
Recommended review
Before unattended agent use, check whether the tool reads plaintext credentials, writes remote state, publishes artifacts, or shells out to plugins.
executables
Installed executables
| Command | Kind | Exposure | Note |
|---|---|---|---|
ocat | cli | global executable |
freshness
Version and freshness
These signals separate page generation age, package-manager activity, and upstream release comparison. Version lag is warned only when an evidence URL and comparable versions are present.
page generated2026-07-08
manager version4.11.0
manager updated
local dataok
upstreamcurrent
latest detectedv4.11.0
https://github.com/rahra/onioncat
- infoNo package-manager update timestamp was available.low confidence
install metadata
Package metadata
| Package key | brew:onioncat |
|---|---|
| Version | 4.11.0 |
| Package manager | Homebrew |
| Package manager page | https://formulae.brew.sh/formula/onioncat |
| Homepage | https://github.com/rahra/onioncat |
| Repository | https://github.com/rahra/onioncat |
| Upstream docs | https://github.com/rahra/onioncat#readme |
| License | GPL-3.0-only |
| Source archive | https://github.com/rahra/onioncat/archive/refs/tags/v4.11.0.tar.gz |
| Dependencies | tor |
| Build dependencies | autoconf, automake |
| Bottle | available (on arm64_big_sur, arm64_linux, arm64_monterey, arm64_sequoia, arm64_sonoma, arm64_tahoe, arm64_ventura, big_sur, monterey, sonoma, ventura, x86_64_linux) |
| Homebrew post-install | not defined |
| Service | none declared |
registry facts
Source database details
| Source Database | Homebrew formula API |
|---|---|
| Tap | homebrew/core |
| Full Name | onioncat |
| Version Scheme | 0 |
| Revision | 0 |
| Head Version | HEAD |
| Bottle Stable Root URL | https://ghcr.io/v2/homebrew/core |
| Deprecated | no |
| Disabled | no |
| Keg Only | no |
| URL Keys |
|
source database matches
Other package-manager records
Matches are pulled from external package-manager indexes and kept separate from local Automic Vault package links.
apk95%
onioncat 4.11.0-r1
OnionCat is a VPN-adapter, which uses Tor or I2P as its transport.
sudo apk add onioncat- License: GPL-3.0-only
- Architecture: x86_64
- Source Package: onioncat
- 1 dependencies
- 1 provides
- normalized package name match
- Matched by: Onioncat
apk95%
onioncat-doc 4.11.0-r1
OnionCat is a VPN-adapter, which uses Tor or I2P as its transport. (documentation)
sudo apk add onioncat-doc- License: GPL-3.0-only
- Architecture: x86_64
- Source Package: onioncat
- normalized package name match
- Matched by: Onioncat
zypper95%
onioncat 4.11.0-1.10
VPN adapter for Tor and I2P
sudo zypper install onioncat- License: GPL-3.0-only
- Category: Unspecified
- Architecture: x86_64
- Source Package: onioncat
- 2 dependencies
- 1 provides
- normalized package name match
- Matched by: Onioncat
MacPorts95%
onioncat
sudo port install onioncat- normalized package name match
- Matched by: Onioncat
Scoop92%
extras/ocat
scoop install extras/ocat- installed executable or alias match
- Matched by: Ocat
winget92%
ic005k.OCAuxiliaryTools
winget install --id ic005k.OCAuxiliaryTools -e- installed executable or alias match
- Matched by: Ocat
source trail
Generated from repository data
This page is generated by av-web from the private package SQLite artifact built by scripts/generate-pkg-sqlite.py.
Combined YAML source
View the package source record on GitHub.
Used sources
- Geiger risk classifier
- Nucleus package database
- av.db category and tag curation
- cross-ecosystem install command graph
- curated package history
- external package-manager database matches
- package relationship graph
- package version freshness
- package-page enrichment