anonymize MAC: remove the dhcp-client-id settings again

Having a random DHCP client identifier sticks out in network
dumps and thus contradicts privacy intentions.

Instead, stick to the default of sending the already random
MAC.
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3hhh 2022-11-19 10:03:58 +01:00
parent 86c708cc3b
commit 839d8c4314
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@ -23,7 +23,7 @@ Save the change and reconnect the connection (click on Network Manager tray icon
These steps should be done inside a template to be used to create a NetVM as it relies on creating a config file that would otherwise be deleted after a reboot due to the nature of AppVMs. These steps should be done inside a template to be used to create a NetVM as it relies on creating a config file that would otherwise be deleted after a reboot due to the nature of AppVMs.
Write the settings to a new file in the `/etc/NetworkManager/conf.d/` directory, such as `00-macrandomize.conf`. Write the settings to a new file in the `/etc/NetworkManager/conf.d/` directory, such as `50-macrandomize.conf`.
The following example enables Wi-Fi and Ethernet MAC address randomization while scanning (not connected), and uses a randomly generated but persistent MAC address for each individual Wi-Fi and Ethernet connection profile. The following example enables Wi-Fi and Ethernet MAC address randomization while scanning (not connected), and uses a randomly generated but persistent MAC address for each individual Wi-Fi and Ethernet connection profile.
It was inspired by the [official NetworkManager example](https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/blob/main/examples/nm-conf.d/30-anon.conf). It was inspired by the [official NetworkManager example](https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/blob/main/examples/nm-conf.d/30-anon.conf).
@ -36,15 +36,12 @@ wifi.cloned-mac-address=stable
ethernet.cloned-mac-address=stable ethernet.cloned-mac-address=stable
connection.stable-id=${CONNECTION}/${BOOT} connection.stable-id=${CONNECTION}/${BOOT}
#the below settings are optional (see the explanations below) #the below settings is optional (see the explanations below)
ipv6.ip6-privacy=2 ipv6.ip6-privacy=2
ipv4.dhcp-client-id=stable
ipv6.dhcp-duid=stable-uuid
~~~ ~~~
* `cloned-mac-address=stable` in combination with `connection.stable-id=${CONNECTION}/${BOOT}` generates a random MAC address that persists until reboot. You could use `connection.stable-id=random` instead, which generates a random MAC address each time a link goes up. * `cloned-mac-address=stable` in combination with `connection.stable-id=${CONNECTION}/${BOOT}` generates a random MAC address that persists until reboot. You could use `connection.stable-id=random` instead, which generates a random MAC address each time a link goes up.
* `ipv6.ip6-privacy=2` will cause multiple random IPv6 addresses to be used during every session (cf. [RFC 4941](https://datatracker.ietf.org/doc/html/rfc4941)). If you want to use a fixed IPv6 address based on the already random MAC address, choose `ipv6.ip6-privacy=0`. Leaving this setting at the default is not recommended as it is basically undefined. * `ipv6.ip6-privacy=2` will cause multiple random IPv6 addresses to be used during every session (cf. [RFC 4941](https://datatracker.ietf.org/doc/html/rfc4941)). If you want to use a fixed IPv6 address based on the already random MAC address, choose `ipv6.ip6-privacy=0`. Leaving this setting at the default is not recommended as it is basically undefined.
* `ipv4.dhcp-client-id=stable` and `ipv6.dhcp-duid=stable-uuid` instruct `NetworkManager` to use a DHCP client identifier based upon the random MAC address. According to the current `NetworkManager` documentation the default is undefined. So it makes sense to set one explicitly.
Also make sure that you have `addr-gen-mode=stable-privacy` in the `[ipv6]` section of your `/rw/config/NM-system-connections/*.nmconnection` files as this setting can only be set per connection. Also make sure that you have `addr-gen-mode=stable-privacy` in the `[ipv6]` section of your `/rw/config/NM-system-connections/*.nmconnection` files as this setting can only be set per connection.