cloud-init/tools/write-ssh-key-fingerprints
Scott Moser efda2350a9 output public ssh host keys to console on boot (LP: #893400)
Currently cloud-init writes something like this to console output:
  ec2: #############################################################
  ec2: -----BEGIN SSH HOST KEY FINGERPRINTS-----
  ec2: 2048 78:ae:f3:91:04:6f:8d:ee:ef:e1:2d:72:83:6a:d0:82  root@h (RSA)
  ec2: 1024 d3:b6:32:64:22:d4:43:05:f9:25:b4:f3:65:4e:e2:51  root@h (DSA)
  ec2: -----END SSH HOST KEY FINGERPRINTS-----
  ec2: #############################################################

the key fingerprints are useful for humans to read, but not so useful
for machines, as you cannot populate a KnownHostsFile (~/.ssh/known_hosts)
from the data there.

This change adds output like:
  -----BEGIN SSH HOST KEY KEYS-----
  ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdH......STI= root@h
  ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDYRIQe6m......tWF3 root@h
  -----END SSH HOST KEY KEYS-----

Those lines can easily be grabbed and appended to a known_hosts file.
2011-12-20 00:13:07 -05:00

29 lines
863 B
Bash
Executable File

#!/bin/sh
fp_blist=",${1},"
key_blist=",${2},"
{
echo
echo "#############################################################"
echo "-----BEGIN SSH HOST KEY FINGERPRINTS-----"
for f in /etc/ssh/ssh_host_*key.pub; do
[ -f "$f" ] || continue
read ktype line < "$f"
# skip the key if its type is in the blacklist
[ "${fp_blist#*,$ktype,}" = "${fp_blist}" ] || continue
ssh-keygen -l -f "$f"
done
echo "-----END SSH HOST KEY FINGERPRINTS-----"
echo "#############################################################"
} | logger -p user.info -s -t "ec2"
echo -----BEGIN SSH HOST KEY KEYS-----
for f in /etc/ssh/ssh_host_*key.pub; do
[ -f "$f" ] || continue
read ktype line < "$f"
# skip the key if its type is in the blacklist
[ "${key_blist#*,$ktype,}" = "${key_blist}" ] || continue
cat $f
done
echo -----END SSH HOST KEY KEYS-----