Tod Beardsley
810133acc2
Note that net-ssh is no longer actively maintained: http://weblog.jamisbuck.org/2009/2/25/net-ssh-capistrano-and-saying-goodbye git-svn-id: file:///home/svn/framework3/trunk@8523 4d416f70-5f16-0410-b530-b9f4589650da
53 lines
2.0 KiB
Ruby
53 lines
2.0 KiB
Ruby
require 'net/ssh/errors'
|
|
require 'net/ssh/known_hosts'
|
|
|
|
module Net; module SSH; module Verifiers
|
|
|
|
# Does a strict host verification, looking the server up in the known
|
|
# host files to see if a key has already been seen for this server. If this
|
|
# server does not appear in any host file, this will silently add the
|
|
# server. If the server does appear at least once, but the key given does
|
|
# not match any known for the server, an exception will be raised (HostKeyMismatch).
|
|
# Otherwise, this returns true.
|
|
class Strict
|
|
def verify(arguments)
|
|
options = arguments[:session].options
|
|
host = options[:host_key_alias] || arguments[:session].host_as_string
|
|
matches = Net::SSH::KnownHosts.search_for(host, arguments[:session].options)
|
|
|
|
# we've never seen this host before, so just automatically add the key.
|
|
# not the most secure option (since the first hit might be the one that
|
|
# is hacked), but since almost nobody actually compares the key
|
|
# fingerprint, this is a reasonable compromise between usability and
|
|
# security.
|
|
if matches.empty?
|
|
ip = arguments[:session].peer[:ip]
|
|
Net::SSH::KnownHosts.add(host, arguments[:key], arguments[:session].options)
|
|
return true
|
|
end
|
|
|
|
# If we found any matches, check to see that the key type and
|
|
# blob also match.
|
|
found = matches.any? do |key|
|
|
key.ssh_type == arguments[:key].ssh_type &&
|
|
key.to_blob == arguments[:key].to_blob
|
|
end
|
|
|
|
# If a match was found, return true. Otherwise, raise an exception
|
|
# indicating that the key was not recognized.
|
|
found || process_cache_miss(host, arguments)
|
|
end
|
|
|
|
private
|
|
|
|
def process_cache_miss(host, args)
|
|
exception = HostKeyMismatch.new("fingerprint #{args[:fingerprint]} does not match for #{host.inspect}")
|
|
exception.data = args
|
|
exception.callback = Proc.new do
|
|
Net::SSH::KnownHosts.add(host, args[:key], args[:session].options)
|
|
end
|
|
raise exception
|
|
end
|
|
end
|
|
|
|
end; end; end |