louisna / pyroute2

Python Netlink and PF_ROUTE library — network setup and monitoring

Pyroute2

Pyroute2 is a pure Python netlink library. The core requires only Python stdlib, no 3rd party libraries. The library was started as an RTNL protocol implementation, so the name is pyroute2, but now it supports many netlink protocols. Some supported netlink families and protocols:

• rtnl, network settings --- addresses, routes, traffic controls
• nfnetlink --- netfilter API
• ipq --- simplest userspace packet filtering, iptables QUEUE target
• devlink --- manage and monitor devlink-enabled hardware
• generic --- generic netlink families
• uevent --- same uevent messages as in udev

Netfilter API:

• ipset --- IP sets
• nftables --- packet filtering
• nfct --- connection tracking

Generic netlink:

• ethtool --- low-level network interface setup
• wireguard --- VPN setup
• nl80211 --- wireless functions API (basic support)
• taskstats --- extended process statistics
• acpi_events --- ACPI events monitoring
• thermal_events --- thermal events monitoring
• VFS_DQUOT --- disk quota events monitoring

On the low level the library provides socket objects with an extended API. The additional functionality aims to:

• Help to open/bind netlink sockets
• Discover generic netlink protocols and multicast groups
• Construct, encode and decode netlink and PF_ROUTE messages

Supported systems

Pyroute2 runs natively on Linux and emulates some limited subset of RTNL netlink API on BSD systems on top of PF_ROUTE notifications and standard system tools.

Other platforms are not supported.

NDB -- high level RTNL API

Key features:

• Data integrity
• Transactions with commit/rollback changes
• State synchronization
• Multiple sources, including netns and remote systems

A "Hello world" example:

from pyroute2 import NDB

ndb = NDB(log='on')
for record in ndb.interfaces.summary():
    print(record.ifname, record.address, record.state)

for record in ndb.addresses.summary():
    print(record._as_dict())

(ndb
 .interfaces
 .create(ifname='br0', kind='bridge')  # create a bridge
 .add_port('eth0')                     # add ports
 .add_port('eth1')                     #
 .add_ip('10.0.0.1/24')                # add addresses
 .add_ip('192.168.0.1/24')             #
 .set('br_stp_state', 1)               # set STP on
 .set('state', 'up')                   # bring the interface up
 .commit())                            # commit pending changes

IPRoute -- Low level RTNL API

Low-level IPRoute utility --- Linux network configuration. The IPRoute class is a 1-to-1 RTNL mapping. There are no implicit interface lookups and so on.

Get notifications about network settings changes with IPRoute:

from pyroute2 import IPRoute
with IPRoute() as ipr:
    # With IPRoute objects you have to call bind() manually
    ipr.bind()
    for message in ipr.get():
        print(message)

More examples:

from socket import AF_INET
from pyroute2 import IPRoute

# get access to the netlink socket
ip = IPRoute()
# no monitoring here -- thus no bind()

# print interfaces
for link in ip.get_links():
    print(link)

# create VETH pair and move v0p1 to netns 'test'
ip.link('add', ifname='v0p0', peer='v0p1', kind='veth')
idx = ip.link_lookup(ifname='v0p1')[0]
ip.link('set', index=idx, net_ns_fd='test')

# bring v0p0 up and add an address
idx = ip.link_lookup(ifname='v0p0')[0]
ip.link('set', index=idx, state='up')
ip.addr('add', index=idx, address='10.0.0.1', prefixlen=24)

# release Netlink socket
ip.close()

Network namespace examples

Network namespace manipulation:

from pyroute2 import netns
# create netns
netns.create('test')
# list
print(netns.listnetns())
# remove netns
netns.remove('test')

Create veth interfaces pair and move to netns:

from pyroute2 import IPRoute

with IPRoute() as ipr:

    # create interface pair
    ipr.link('add', ifname='v0p0', kind='veth',  peer='v0p1')

    # lookup the peer index
    idx = ipr.link_lookup(ifname='v0p1')[0]

    # move the peer to the 'test' netns:
    ipr.link('set', index='v0p1', net_ns_fd='test')

List interfaces in some netns:

from pyroute2 import NetNS
from pprint import pprint

ns = NetNS('test')
pprint(ns.get_links())
ns.close()

More details and samples see in the documentation.

Installation

make install or pip install pyroute2

Requirements

Python >= 2.7

The pyroute2 testing and documentaion framework requirements:

• flake8
• coverage
• nosetests
• sphinx
• aafigure
• netaddr
• dtcd (optional, https://github.com/svinota/dtcd)

Optional dependencies:

• mitogen -- for distributed rtnl
• psutil -- for ss2 tool

Links

• home: https://pyroute2.org/
• srcs: https://github.com/svinota/pyroute2
• bugs: https://github.com/svinota/pyroute2/issues
• pypi: https://pypi.python.org/pypi/pyroute2
• docs: http://docs.pyroute2.org/