nsproxy (namespace proxy) is a Linux-specific tool that forces apps to use a specific SOCKS5 or HTTP proxy.

Functionally similar to proxychains / tsocks / graftcp, it takes a different approach by using Linux namespaces + TUN device + user-mode TCP/IP stack.

It has the following features:

• Supports SOCKS5 / HTTP proxy protocols.
• Supports TCP / UDP protocols.
• Supports DNS redirection.
• Works on statically linked programs or forked processes.
• No privileges or capabilities required.
• No system-wide side effects.

BUILD

cmake -S . -B build -DCMAKE_BUILD_TYPE=Release cmake --build build sudo cmake --install build # Optional

USAGE

Usage: nsproxy [OPTIONS...] [ARGS...]

Examples:

Run curl with SOCKS proxy

nsproxy -s 192.168.1.100 -p 1080 curl http://example.com

Run curl with HTTP proxy

nsproxy -H -s 192.168.1.100 -p 8080 curl http://example.com

Common Options: -H Use an HTTP proxy instead of SOCKS5 -s Set the proxy server address -p Set the proxy server port -d Redirect DNS queries to <tcp|udp>://[:PORT] or "off" -a user:pass Set the proxy username and password -6 Enable IPv6 support -v Increase verbosity -q Be quiet

For more details, see the man page.

LIMITATIONS

All UIDs and GIDs except the current user's are mapped to the overflow UID/GID. This means programs like sudo or su will not work.

It's unable to establish a connection from the outside to the inside. This means programs listening on a port like apache or nginx will not work.

Connections to loopback addresses (127.0.0.1) refer to the inside of the namespace, not the host.

CREDITS

lwip - A Lightweight TCP/IP stack https://savannah.nongnu.org/projects/lwip/

slirp4netns - User-mode networking for unprivileged network namespaces https://github.com/rootless-containers/slirp4netns

LICENSE

Copyright (C) 2023 NaLan ZeYu nalanzeyu@gmail.com

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.