From 3b8c7424d1948e52bc2afe0e41e3b64db3f2c22b Mon Sep 17 00:00:00 2001
From: AmineChikhaoui <amine.chikhaoui91@gmail.com>
Date: Sat, 28 Apr 2018 16:52:46 +0100
Subject: [PATCH] pull the ssh host keys from the metadata service as expected
 by NixOps. Issues: #38623 https://github.com/NixOS/nixops/issues/930.

---
 .../modules/virtualisation/google-compute-image.nix | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/nixos/modules/virtualisation/google-compute-image.nix b/nixos/modules/virtualisation/google-compute-image.nix
index 0b6bec786da4..e0d8027c67aa 100644
--- a/nixos/modules/virtualisation/google-compute-image.nix
+++ b/nixos/modules/virtualisation/google-compute-image.nix
@@ -221,7 +221,7 @@ in
           echo "Obtaining SSH keys..."
           mkdir -m 0700 -p /root/.ssh
           AUTH_KEYS=$(${mktemp})
-          ${wget} -O $AUTH_KEYS --header="Metadata-Flavor: Google" http://metadata.google.internal/computeMetadata/v1/instance/attributes/sshKeys
+          ${wget} -O $AUTH_KEYS http://metadata.google.internal/computeMetadata/v1/instance/attributes/sshKeys
           if [ -s $AUTH_KEYS ]; then
 
             # Read in key one by one, split in case Google decided
@@ -246,6 +246,17 @@ in
             false
           fi
           rm -f $AUTH_KEYS
+          SSH_HOST_KEYS_DIR=$(${mktemp} -d)
+          ${wget} -O $SSH_HOST_KEYS_DIR/ssh_host_ed25519_key http://metadata.google.internal/computeMetadata/v1/instance/attributes/ssh_host_ed25519_key
+          ${wget} -O $SSH_HOST_KEYS_DIR/ssh_host_ed25519_key.pub http://metadata.google.internal/computeMetadata/v1/instance/attributes/ssh_host_ed25519_key_pub
+          if [ -s $SSH_HOST_KEYS_DIR/ssh_host_ed25519_key -a -s $SSH_HOST_KEYS_DIR/ssh_host_ed25519_key.pub ]; then
+              mv -f $SSH_HOST_KEYS_DIR/ssh_host_ed25519_key* /etc/ssh/
+              chmod 600 /etc/ssh/ssh_host_ed25519_key
+              chmod 644 /etc/ssh/ssh_host_ed25519_key.pub
+          else
+              echo "Setup of ssh host keys from http://metadata.google.internal/computeMetadata/v1/instance/attributes/ failed."
+          fi
+          rm -f $SSH_HOST_KEYS_DIR/*
         '';
       serviceConfig.Type = "oneshot";
       serviceConfig.RemainAfterExit = true;