From 470d1918ab6fbd67b540565b1723d4de9f22554d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= <joerg@thalheim.io>
Date: Sun, 7 May 2023 21:06:12 +0200
Subject: [PATCH] kexec-installer: build variants

---
 build-images.sh                |   2 +-
 flake.nix                      |  20 +++-
 nix/kexec-installer/module.nix | 195 +++++++++++++++++----------------
 3 files changed, 120 insertions(+), 97 deletions(-)

diff --git a/build-images.sh b/build-images.sh
index d839870..2f77f52 100755
--- a/build-images.sh
+++ b/build-images.sh
@@ -22,7 +22,7 @@ build_netboot_image() {
 build_kexec_installer() {
   declare -r tag=$1 arch=$2 tmp=$3 variant=$4
   out=$(nix build --print-out-paths --option accept-flake-config true -L ".#packages.${arch}.kexec-installer-${tag//.}${variant}")
-  echo "$out/nixos-kexec-installer-$arch.tar.gz"
+  echo "$out/nixos-kexec-installer${variant}-$arch.tar.gz"
 }
 
 main() {
diff --git a/flake.nix b/flake.nix
index 236464a..4811391 100644
--- a/flake.nix
+++ b/flake.nix
@@ -24,11 +24,23 @@
       kexec-installer-nixos-unstable = kexec-installer nixos-unstable [];
       kexec-installer-nixos-2211 = kexec-installer nixos-2211 [];
 
-      kexec-installer-nixos-unstable-noninteractive = kexec-installer nixos-unstable [ self.nixosModules.noninteractive ];
-      kexec-installer-nixos-2211-noninteractive = kexec-installer nixos-2211 [ self.nixosModules.noninteractive ];
+      kexec-installer-nixos-unstable-noninteractive = kexec-installer nixos-unstable [ 
+        { system.kexec-installer.name = "kexec-installer-noninteractive"; }
+        self.nixosModules.noninteractive 
+      ];
+      kexec-installer-nixos-2211-noninteractive = kexec-installer nixos-2211 [ 
+        { system.kexec-installer.name = "kexec-installer-noninteractive"; }
+        self.nixosModules.noninteractive 
+      ];
 
-      kexec-installer-nixos-unstable-virtual-noninteractive = kexec-installer nixos-unstable [ self.nixosModules.noninteractive self.nixosModules.virtual ];
-      kexec-installer-nixos-2211-virtual-noninteractive = kexec-installer nixos-2211 [ self.nixosModules.noninteractive self.nixosModules.virtual ];
+      kexec-installer-nixos-unstable-virtual-noninteractive = kexec-installer nixos-unstable [ 
+        { system.kexec-installer.name = "kexec-installer-virtual-noninteractive"; }
+        self.nixosModules.noninteractive self.nixosModules.virtual 
+      ];
+      kexec-installer-nixos-2211-virtual-noninteractive = kexec-installer nixos-2211 [ 
+        { system.kexec-installer.name = "kexec-installer-virtual-noninteractive"; }
+        self.nixosModules.noninteractive self.nixosModules.virtual 
+      ];
     });
     nixosModules = {
       kexec-installer = ./nix/kexec-installer/module.nix;
diff --git a/nix/kexec-installer/module.nix b/nix/kexec-installer/module.nix
index 494f1ba..df2a7d7 100644
--- a/nix/kexec-installer/module.nix
+++ b/nix/kexec-installer/module.nix
@@ -10,104 +10,115 @@ in {
   imports = [
     (modulesPath + "/installer/netboot/netboot-minimal.nix")
   ];
-
-  # We are stateless, so just default to latest.
-  system.stateVersion = config.system.nixos.version;
-
-  # This is a variant of the upstream kexecScript that also allows embedding
-  # a ssh key.
-  system.build.kexecRun = pkgs.runCommand "kexec-run" {} ''
-    install -D -m 0755 ${./kexec-run.sh} $out
-
-    sed -i \
-      -e 's|@init@|${config.system.build.toplevel}/init|' \
-      -e 's|@kernelParams@|${lib.escapeShellArgs config.boot.kernelParams}|' \
-      $out
-
-    ${pkgs.shellcheck}/bin/shellcheck $out
-  '';
-
-  system.build.kexecTarball = pkgs.runCommand "kexec-tarball" {} ''
-    mkdir kexec $out
-    cp "${config.system.build.netbootRamdisk}/initrd" kexec/initrd
-    cp "${config.system.build.kernel}/${config.system.boot.loader.kernelFile}" kexec/bzImage
-    cp "${config.system.build.kexecRun}" kexec/run
-    cp "${pkgs.pkgsStatic.kexec-tools}/bin/kexec" kexec/kexec
-    cp "${iprouteStatic}/bin/ip" kexec/ip
-    tar -czvf $out/nixos-kexec-installer-${pkgs.stdenv.hostPlatform.system}.tar.gz kexec
-  '';
-
-  # IPMI SOL console redirection stuff
-  boot.kernelParams =
-    [ "console=tty0" ] ++
-    (lib.optional (pkgs.stdenv.hostPlatform.isAarch32 || pkgs.stdenv.hostPlatform.isAarch64) "console=ttyAMA0,115200") ++
-    (lib.optional (pkgs.stdenv.hostPlatform.isRiscV) "console=ttySIF0,115200") ++
-    [ "console=ttyS0,115200" ];
-
-  documentation.enable = false;
-  # Not really needed. Saves a few bytes and the only service we are running is sshd, which we want to be reachable.
-  networking.firewall.enable = false;
-
-  systemd.network.enable = true;
-  networking.dhcpcd.enable = false;
-
-  # for detection if we are on kexec
-  environment.etc.is_kexec.text = "true";
-
-  # for zapping of disko
-  environment.systemPackages = [
-    pkgs.jq
-  ];
-
-  systemd.services.restore-network = {
-    before = [ "network-pre.target" ];
-    wants = [ "network-pre.target" ];
-    wantedBy = [ "multi-user.target" ];
-
-    serviceConfig = {
-      Type = "oneshot";
-      RemainAfterExit = true;
-      ExecStart = [
-        "${restore-network} /root/network/addrs.json /root/network/routes-v4.json /root/network/routes-v6.json /etc/systemd/network"
-      ];
+  options = {
+    system.kexec-installer.name = lib.mkOption {
+      type = lib.types.str;
+      default = "nixos-kexec-installer";
+      description = ''
+        The variant of the kexec installer to use.
+      '';
     };
+  };
 
-    unitConfig.ConditionPathExists = [
-      "/root/network/addrs.json"
-      "/root/network/routes-v4.json"
-      "/root/network/routes-v6.json"
+  config = {
+    # We are stateless, so just default to latest.
+    system.stateVersion = config.system.nixos.version;
+
+    # This is a variant of the upstream kexecScript that also allows embedding
+    # a ssh key.
+    system.build.kexecRun = pkgs.runCommand "kexec-run" {} ''
+      install -D -m 0755 ${./kexec-run.sh} $out
+
+      sed -i \
+        -e 's|@init@|${config.system.build.toplevel}/init|' \
+        -e 's|@kernelParams@|${lib.escapeShellArgs config.boot.kernelParams}|' \
+        $out
+
+      ${pkgs.shellcheck}/bin/shellcheck $out
+    '';
+
+    system.build.kexecTarball = pkgs.runCommand "kexec-tarball" {} ''
+      mkdir kexec $out
+      cp "${config.system.build.netbootRamdisk}/initrd" kexec/initrd
+      cp "${config.system.build.kernel}/${config.system.boot.loader.kernelFile}" kexec/bzImage
+      cp "${config.system.build.kexecRun}" kexec/run
+      cp "${pkgs.pkgsStatic.kexec-tools}/bin/kexec" kexec/kexec
+      cp "${iprouteStatic}/bin/ip" kexec/ip
+      tar -czvf $out/${config.system.kexec-installer.name}-${pkgs.stdenv.hostPlatform.system}.tar.gz kexec
+    '';
+
+    # IPMI SOL console redirection stuff
+    boot.kernelParams =
+      [ "console=tty0" ] ++
+      (lib.optional (pkgs.stdenv.hostPlatform.isAarch32 || pkgs.stdenv.hostPlatform.isAarch64) "console=ttyAMA0,115200") ++
+      (lib.optional (pkgs.stdenv.hostPlatform.isRiscV) "console=ttySIF0,115200") ++
+      [ "console=ttyS0,115200" ];
+
+    documentation.enable = false;
+    # Not really needed. Saves a few bytes and the only service we are running is sshd, which we want to be reachable.
+    networking.firewall.enable = false;
+
+    systemd.network.enable = true;
+    networking.dhcpcd.enable = false;
+
+    # for detection if we are on kexec
+    environment.etc.is_kexec.text = "true";
+
+    # for zapping of disko
+    environment.systemPackages = [
+      pkgs.jq
     ];
-  };
 
-  systemd.services.log-network-status = {
-    wantedBy = [ "multi-user.target" ];
-    # No point in restarting this. We just need this after boot
-    restartIfChanged = false;
+    systemd.services.restore-network = {
+      before = [ "network-pre.target" ];
+      wants = [ "network-pre.target" ];
+      wantedBy = [ "multi-user.target" ];
 
-    serviceConfig = {
-      Type = "oneshot";
-      StandardOutput = "journal+console";
-      ExecStart = [
-        # Allow failures, so it still prints what interfaces we have even if we
-        # not get online
-        "-${pkgs.systemd}/lib/systemd/systemd-networkd-wait-online"
-        "${pkgs.iproute2}/bin/ip -c addr"
-        "${pkgs.iproute2}/bin/ip -c -6 route"
-        "${pkgs.iproute2}/bin/ip -c -4 route"
+      serviceConfig = {
+        Type = "oneshot";
+        RemainAfterExit = true;
+        ExecStart = [
+          "${restore-network} /root/network/addrs.json /root/network/routes-v4.json /root/network/routes-v6.json /etc/systemd/network"
+        ];
+      };
+
+      unitConfig.ConditionPathExists = [
+        "/root/network/addrs.json"
+        "/root/network/routes-v4.json"
+        "/root/network/routes-v6.json"
       ];
     };
-  };
 
-  # Restore ssh host and user keys if they are available.
-  # This avoids warnings of unknown ssh keys.
-  boot.initrd.postMountCommands = ''
-    mkdir -m 700 -p /mnt-root/root/.ssh
-    mkdir -m 755 -p /mnt-root/etc/ssh
-    mkdir -m 755 -p /mnt-root/root/network
-    if [[ -f ssh/authorized_keys ]]; then
-      install -m 400 ssh/authorized_keys /mnt-root/root/.ssh
-    fi
-    install -m 400 ssh/ssh_host_* /mnt-root/etc/ssh
-    cp *.json /mnt-root/root/network/
-  '';
+    systemd.services.log-network-status = {
+      wantedBy = [ "multi-user.target" ];
+      # No point in restarting this. We just need this after boot
+      restartIfChanged = false;
+
+      serviceConfig = {
+        Type = "oneshot";
+        StandardOutput = "journal+console";
+        ExecStart = [
+          # Allow failures, so it still prints what interfaces we have even if we
+          # not get online
+          "-${pkgs.systemd}/lib/systemd/systemd-networkd-wait-online"
+          "${pkgs.iproute2}/bin/ip -c addr"
+          "${pkgs.iproute2}/bin/ip -c -6 route"
+          "${pkgs.iproute2}/bin/ip -c -4 route"
+        ];
+      };
+    };
+
+    # Restore ssh host and user keys if they are available.
+    # This avoids warnings of unknown ssh keys.
+    boot.initrd.postMountCommands = ''
+      mkdir -m 700 -p /mnt-root/root/.ssh
+      mkdir -m 755 -p /mnt-root/etc/ssh
+      mkdir -m 755 -p /mnt-root/root/network
+      if [[ -f ssh/authorized_keys ]]; then
+        install -m 400 ssh/authorized_keys /mnt-root/root/.ssh
+      fi
+      install -m 400 ssh/ssh_host_* /mnt-root/etc/ssh
+      cp *.json /mnt-root/root/network/
+    '';
+  };
 }