pyrox.dev
1# This module defines a systemd service that sets the SSH host key and
2# authorized client key and host name of virtual machines running on
3# Amazon EC2, Eucalyptus and OpenStack Compute (Nova).
4
5{ config, lib, pkgs, ... }:
6
7with lib;
8
9{
10 imports = [
11 (mkRemovedOptionModule [ "ec2" "metadata" ] "")
12 ];
13
14 config = {
15
16 systemd.services.apply-ec2-data =
17 { description = "Apply EC2 Data";
18
19 wantedBy = [ "multi-user.target" "sshd.service" ];
20 before = [ "sshd.service" ];
21 after = ["fetch-ec2-metadata.service"];
22
23 path = [ pkgs.iproute2 ];
24
25 script =
26 ''
27 ${optionalString (config.networking.hostName == "") ''
28 echo "setting host name..."
29 if [ -s /etc/ec2-metadata/hostname ]; then
30 ${pkgs.nettools}/bin/hostname $(cat /etc/ec2-metadata/hostname)
31 fi
32 ''}
33
34 if ! [ -e /root/.ssh/authorized_keys ]; then
35 echo "obtaining SSH key..."
36 mkdir -m 0700 -p /root/.ssh
37 if [ -s /etc/ec2-metadata/public-keys-0-openssh-key ]; then
38 cat /etc/ec2-metadata/public-keys-0-openssh-key >> /root/.ssh/authorized_keys
39 echo "new key added to authorized_keys"
40 chmod 600 /root/.ssh/authorized_keys
41 fi
42 fi
43
44 # Extract the intended SSH host key for this machine from
45 # the supplied user data, if available. Otherwise sshd will
46 # generate one normally.
47 userData=/etc/ec2-metadata/user-data
48
49 mkdir -m 0755 -p /etc/ssh
50
51 if [ -s "$userData" ]; then
52 key="$(sed 's/|/\n/g; s/SSH_HOST_DSA_KEY://; t; d' $userData)"
53 key_pub="$(sed 's/SSH_HOST_DSA_KEY_PUB://; t; d' $userData)"
54 if [ -n "$key" -a -n "$key_pub" -a ! -e /etc/ssh/ssh_host_dsa_key ]; then
55 (umask 077; echo "$key" > /etc/ssh/ssh_host_dsa_key)
56 echo "$key_pub" > /etc/ssh/ssh_host_dsa_key.pub
57 fi
58
59 key="$(sed 's/|/\n/g; s/SSH_HOST_ED25519_KEY://; t; d' $userData)"
60 key_pub="$(sed 's/SSH_HOST_ED25519_KEY_PUB://; t; d' $userData)"
61 if [ -n "$key" -a -n "$key_pub" -a ! -e /etc/ssh/ssh_host_ed25519_key ]; then
62 (umask 077; echo "$key" > /etc/ssh/ssh_host_ed25519_key)
63 echo "$key_pub" > /etc/ssh/ssh_host_ed25519_key.pub
64 fi
65 fi
66 '';
67
68 serviceConfig.Type = "oneshot";
69 serviceConfig.RemainAfterExit = true;
70 };
71
72 systemd.services.print-host-key =
73 { description = "Print SSH Host Key";
74 wantedBy = [ "multi-user.target" ];
75 after = [ "sshd.service" ];
76 script =
77 ''
78 # Print the host public key on the console so that the user
79 # can obtain it securely by parsing the output of
80 # ec2-get-console-output.
81 echo "-----BEGIN SSH HOST KEY FINGERPRINTS-----" > /dev/console
82 for i in /etc/ssh/ssh_host_*_key.pub; do
83 ${config.programs.ssh.package}/bin/ssh-keygen -l -f $i > /dev/console
84 done
85 echo "-----END SSH HOST KEY FINGERPRINTS-----" > /dev/console
86 '';
87 serviceConfig.Type = "oneshot";
88 serviceConfig.RemainAfterExit = true;
89 };
90
91 };
92}