mirror of
https://github.com/alrayyes/wiki.git
synced 2024-11-25 21:16:21 +00:00
37 lines
1.4 KiB
Markdown
37 lines
1.4 KiB
Markdown
---
|
|
date: 2022-02-19
|
|
id: 516b5872-de3c-4d22-bf28-435778c85516
|
|
title: IPv6
|
|
---
|
|
|
|
# Privacy extensions
|
|
|
|
When a client acquires an address through SLAAC its IPv6 address is
|
|
derived from the advertised prefix and the MAC address of the network
|
|
interface of the client. This may raise security concerns as the MAC
|
|
address of the computer can be easily derived by the IPv6 address. In
|
|
order to tackle this problem the IPv6 Privacy Extensions standard (RFC
|
|
4941[^1]) has been developed. With privacy extensions the kernel
|
|
generates a temporary address that is mangled from the original
|
|
autoconfigured address. Private addresses are preferred when connecting
|
|
to a remote server so the original address is hidden. To enable Privacy
|
|
Extensions reproduce add these lines to /etc/sysctl.d/40-ipv6.conf:
|
|
|
|
# Enable IPv6 Privacy Extensions
|
|
net.ipv6.conf.all.use_tempaddr = 2
|
|
net.ipv6.conf.default.use_tempaddr = 2
|
|
net.ipv6.conf.nic0.use_tempaddr = 2
|
|
...
|
|
net.ipv6.conf.nicN.use_tempaddr = 2
|
|
|
|
Where `nic0` to `nicN` are your Network Interface Cards. The
|
|
`all.use_tempaddr` or `default.use_tempaddr` parameters are not applied
|
|
to nic's that already exist when the sysctl settings are executed.
|
|
|
|
After a reboot, at the latest, Privacy Extensions should be enabled.
|
|
NetworkManager should automatically enable `ipv6.ip6-privacy` by reading
|
|
`/proc/sys/net/ipv6/conf/default/use_tempaddr`.
|
|
|
|
# Footnotes
|
|
|
|
[^1]: <https://tools.ietf.org/html/rfc4941>
|