blob: 93a83a3e42af4dfda0dba2218833e414adcf1ee3 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
# This module defines a systemd service that obtains the SSH key and
# host name of virtual machines running on Amazon EC2, Eucalyptus and
# OpenStack Compute (Nova).
{ config, lib, pkgs, ... }:
with lib;
{
options = {
ec2.metadata = mkOption {
type = types.bool;
default = false;
description = ''
Whether to allow access to EC2 metadata.
'';
};
};
config = {
systemd.services."fetch-ec2-data" =
{ description = "Fetch EC2 Data";
wantedBy = [ "multi-user.target" "sshd.service" ];
before = [ "sshd.service" ];
wants = [ "ip-up.target" ];
after = [ "ip-up.target" ];
path = [ pkgs.wget pkgs.iproute ];
script =
''
ip route del blackhole 169.254.169.254/32 || true
wget="wget -q --retry-connrefused -O -"
echo "setting host name..."
${optionalString (config.networking.hostName == "") ''
${pkgs.nettools}/bin/hostname $($wget http://169.254.169.254/1.0/meta-data/hostname)
''}
# Don't download the SSH key if it has already been injected
# into the image (a Nova feature).
if ! [ -e /root/.ssh/authorized_keys ]; then
echo "obtaining SSH key..."
mkdir -p /root/.ssh
$wget http://169.254.169.254/1.0/meta-data/public-keys/0/openssh-key > /root/key.pub
if [ $? -eq 0 -a -e /root/key.pub ]; then
if ! grep -q -f /root/key.pub /root/.ssh/authorized_keys; then
cat /root/key.pub >> /root/.ssh/authorized_keys
echo "new key added to authorized_keys"
fi
chmod 600 /root/.ssh/authorized_keys
rm -f /root/key.pub
fi
fi
# Extract the intended SSH host key for this machine from
# the supplied user data, if available. Otherwise sshd will
# generate one normally.
$wget http://169.254.169.254/2011-01-01/user-data > /root/user-data || true
key="$(sed 's/|/\n/g; s/SSH_HOST_DSA_KEY://; t; d' /root/user-data)"
key_pub="$(sed 's/SSH_HOST_DSA_KEY_PUB://; t; d' /root/user-data)"
if [ -n "$key" -a -n "$key_pub" -a ! -e /etc/ssh/ssh_host_dsa_key ]; then
mkdir -m 0755 -p /etc/ssh
(umask 077; echo "$key" > /etc/ssh/ssh_host_dsa_key)
echo "$key_pub" > /etc/ssh/ssh_host_dsa_key.pub
fi
${optionalString (! config.ec2.metadata) ''
# Since the user data is sensitive, prevent it from being
# accessed from now on.
ip route add blackhole 169.254.169.254/32
''}
'';
serviceConfig.Type = "oneshot";
serviceConfig.RemainAfterExit = true;
};
systemd.services."print-host-key" =
{ description = "Print SSH Host Key";
wantedBy = [ "multi-user.target" ];
after = [ "sshd.service" ];
script =
''
# Print the host public key on the console so that the user
# can obtain it securely by parsing the output of
# ec2-get-console-output.
echo "-----BEGIN SSH HOST KEY FINGERPRINTS-----" > /dev/console
${pkgs.openssh}/bin/ssh-keygen -l -f /etc/ssh/ssh_host_dsa_key.pub > /dev/console
echo "-----END SSH HOST KEY FINGERPRINTS-----" > /dev/console
'';
serviceConfig.Type = "oneshot";
serviceConfig.RemainAfterExit = true;
};
};
}
|