nixpkgs/nixos/modules/system/boot/initrd-network.nix
2022-08-03 22:46:41 +02:00

147 lines
4.3 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.boot.initrd.network;
dhcpInterfaces = lib.attrNames (lib.filterAttrs (iface: v: v.useDHCP == true) (config.networking.interfaces or {}));
doDhcp = config.networking.useDHCP || dhcpInterfaces != [];
dhcpIfShellExpr = if config.networking.useDHCP
then "$(ls /sys/class/net/ | grep -v ^lo$)"
else lib.concatMapStringsSep " " lib.escapeShellArg dhcpInterfaces;
udhcpcScript = pkgs.writeScript "udhcp-script"
''
#! /bin/sh
if [ "$1" = bound ]; then
ip address add "$ip/$mask" dev "$interface"
if [ -n "$mtu" ]; then
ip link set mtu "$mtu" dev "$interface"
fi
if [ -n "$staticroutes" ]; then
echo "$staticroutes" \
| sed -r "s@(\S+) (\S+)@ ip route add \"\1\" via \"\2\" dev \"$interface\" ; @g" \
| sed -r "s@ via \"0\.0\.0\.0\"@@g" \
| /bin/sh
fi
if [ -n "$router" ]; then
ip route add "$router" dev "$interface" # just in case if "$router" is not within "$ip/$mask" (e.g. Hetzner Cloud)
ip route add default via "$router" dev "$interface"
fi
if [ -n "$dns" ]; then
rm -f /etc/resolv.conf
for server in $dns; do
echo "nameserver $server" >> /etc/resolv.conf
done
fi
fi
'';
udhcpcArgs = toString cfg.udhcpc.extraArgs;
in
{
options = {
boot.initrd.network.enable = mkOption {
type = types.bool;
default = false;
description = lib.mdDoc ''
Add network connectivity support to initrd. The network may be
configured using the `ip` kernel parameter,
as described in [the kernel documentation](https://www.kernel.org/doc/Documentation/filesystems/nfs/nfsroot.txt).
Otherwise, if
{option}`networking.useDHCP` is enabled, an IP address
is acquired using DHCP.
You should add the module(s) required for your network card to
boot.initrd.availableKernelModules.
`lspci -v | grep -iA8 'network\|ethernet'`
will tell you which.
'';
};
boot.initrd.network.flushBeforeStage2 = mkOption {
type = types.bool;
default = true;
description = lib.mdDoc ''
Whether to clear the configuration of the interfaces that were set up in
the initrd right before stage 2 takes over. Stage 2 will do the regular network
configuration based on the NixOS networking options.
'';
};
boot.initrd.network.udhcpc.extraArgs = mkOption {
default = [];
type = types.listOf types.str;
description = lib.mdDoc ''
Additional command-line arguments passed verbatim to udhcpc if
{option}`boot.initrd.network.enable` and {option}`networking.useDHCP`
are enabled.
'';
};
boot.initrd.network.postCommands = mkOption {
default = "";
type = types.lines;
description = lib.mdDoc ''
Shell commands to be executed after stage 1 of the
boot has initialised the network.
'';
};
};
config = mkIf cfg.enable {
boot.initrd.kernelModules = [ "af_packet" ];
boot.initrd.extraUtilsCommands = ''
copy_bin_and_libs ${pkgs.klibc}/lib/klibc/bin.static/ipconfig
'';
boot.initrd.preLVMCommands = mkBefore (
# Search for interface definitions in command line.
''
ifaces=""
for o in $(cat /proc/cmdline); do
case $o in
ip=*)
ipconfig $o && ifaces="$ifaces $(echo $o | cut -d: -f6)"
;;
esac
done
''
# Otherwise, use DHCP.
+ optionalString doDhcp ''
# Bring up all interfaces.
for iface in ${dhcpIfShellExpr}; do
echo "bringing up network interface $iface..."
ip link set "$iface" up && ifaces="$ifaces $iface"
done
# Acquire DHCP leases.
for iface in ${dhcpIfShellExpr}; do
echo "acquiring IP address via DHCP on $iface..."
udhcpc --quit --now -i $iface -O staticroutes --script ${udhcpcScript} ${udhcpcArgs}
done
''
+ cfg.postCommands);
boot.initrd.postMountCommands = mkIf cfg.flushBeforeStage2 ''
for iface in $ifaces; do
ip address flush "$iface"
ip link set "$iface" down
done
'';
};
}