diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix index 2dafd19e0b4..fc95f7a8e91 100644 --- a/nixos/modules/module-list.nix +++ b/nixos/modules/module-list.nix @@ -436,6 +436,7 @@ ./system/activation/top-level.nix ./system/boot/coredump.nix ./system/boot/emergency-mode.nix + ./system/boot/initrd-network.nix ./system/boot/kernel.nix ./system/boot/kexec.nix ./system/boot/loader/efi.nix diff --git a/nixos/modules/system/boot/initrd-network.nix b/nixos/modules/system/boot/initrd-network.nix new file mode 100644 index 00000000000..6c6e2fafad4 --- /dev/null +++ b/nixos/modules/system/boot/initrd-network.nix @@ -0,0 +1,149 @@ +{ config, lib, pkgs, ... }: + +with lib; + +let + cfg = config.boot.initrd.network; + +in +{ + + options = { + + boot.initrd.network.enable = mkOption { + type = types.bool; + default = false; + description = '' + Add network connectivity support to initrd. + + Network options are configured via ip kernel + option, according to the kernel documentation. + ''; + }; + + boot.initrd.network.ssh.enable = mkOption { + type = types.bool; + default = false; + description = '' + Start SSH service during initrd boot. It can be used to debug failing + boot on a remote server, enter pasphrase for an encrypted partition etc. + Service is killed when stage-1 boot is finished. + ''; + }; + + boot.initrd.network.ssh.port = mkOption { + type = types.int; + default = 22; + description = '' + Port on which SSH initrd service should listen. + ''; + }; + + boot.initrd.network.ssh.shell = mkOption { + type = types.str; + default = "/bin/ash"; + description = '' + Login shell of the remote user. Can be used to limit actions user can do. + ''; + }; + + boot.initrd.network.ssh.hostRSAKey = mkOption { + type = types.nullOr types.path; + default = null; + description = '' + RSA SSH private key file in the Dropbear format. + + WARNING: This key is contained insecurely in the global Nix store. Do NOT + use your regular SSH host private keys for this purpose or you'll expose + them to regular users! + ''; + }; + + boot.initrd.network.ssh.hostDSSKey = mkOption { + type = types.nullOr types.path; + default = null; + description = '' + DSS SSH private key file in the Dropbear format. + + WARNING: This key is contained insecurely in the global Nix store. Do NOT + use your regular SSH host private keys for this purpose or you'll expose + them to regular users! + ''; + }; + + boot.initrd.network.ssh.hostECDSAKey = mkOption { + type = types.nullOr types.path; + default = null; + description = '' + ECDSA SSH private key file in the Dropbear format. + + WARNING: This key is contained insecurely in the global Nix store. Do NOT + use your regular SSH host private keys for this purpose or you'll expose + them to regular users! + ''; + }; + + boot.initrd.network.ssh.authorizedKeys = mkOption { + type = types.listOf types.str; + default = config.users.extraUsers.root.openssh.authorizedKeys.keys; + description = '' + Authorized keys for the root user on initrd. + ''; + }; + + }; + + config = mkIf cfg.enable { + + boot.initrd.kernelModules = [ "af_packet" ]; + + boot.initrd.extraUtilsCommands = '' + copy_bin_and_libs ${pkgs.mkinitcpio-nfs-utils}/bin/ipconfig + '' + optionalString cfg.ssh.enable '' + copy_bin_and_libs ${pkgs.dropbear}/bin/dropbear + + cp -pv ${pkgs.glibc}/lib/libnss_files.so.* $out/lib + ''; + + boot.initrd.extraUtilsCommandsTest = optionalString cfg.ssh.enable '' + $out/bin/dropbear -V + ''; + + boot.initrd.postEarlyDeviceCommands = '' + # Search for interface definitions in command line + for o in $(cat /proc/cmdline); do + case $o in + ip=*) + ipconfig $o && hasNetwork=1 + ;; + esac + done + '' + optionalString cfg.ssh.enable '' + if [ -n "$hasNetwork" ]; then + mkdir /dev/pts + mount -t devpts devpts /dev/pts + + mkdir -p /etc + echo 'root:x:0:0:root:/root:${cfg.ssh.shell}' > /etc/passwd + echo '${cfg.ssh.shell}' > /etc/shells + echo 'passwd: files' > /etc/nsswitch.conf + + mkdir -p /var/log + touch /var/log/lastlog + + mkdir -p /etc/dropbear + ${optionalString (cfg.ssh.hostRSAKey != null) "ln -s ${cfg.ssh.hostRSAKey} /etc/dropbear/dropbear_rsa_host_key"} + ${optionalString (cfg.ssh.hostDSSKey != null) "ln -s ${cfg.ssh.hostDSSKey} /etc/dropbear/dropbear_dss_host_key"} + ${optionalString (cfg.ssh.hostECDSAKey != null) "ln -s ${cfg.ssh.hostECDSAKey} /etc/dropbear/dropbear_ecdsa_host_key"} + + mkdir -p /root/.ssh + ${concatStrings (map (key: '' + echo -n ${escapeShellArg key} >> /root/.ssh/authorized_keys + '') cfg.ssh.authorizedKeys)} + + dropbear -s -j -k -E -m -p ${toString cfg.ssh.port} + fi + ''; + + }; +}