42 lines
1.2 KiB
Ruby
42 lines
1.2 KiB
Ruby
|
module Spec
|
||
|
|
module Support
|
||
|
|
module Helpers
|
||
|
|
class KeyGeneratorHelper
|
||
|
|
# The components in a openssh .pub / known_host RSA public key.
|
||
|
|
RSA_COMPONENTS = ['ssh-rsa', :e, :n].freeze
|
||
|
|
|
||
|
|
attr_reader :size
|
||
|
|
|
||
|
|
def initialize(size = 2048)
|
||
|
|
@size = size
|
||
|
|
end
|
||
|
|
|
||
|
|
def generate
|
||
|
|
key = OpenSSL::PKey::RSA.generate(size)
|
||
|
|
components = RSA_COMPONENTS.map do |component|
|
||
|
|
key.respond_to?(component) ? encode_mpi(key.public_send(component)) : component
|
||
|
|
end
|
||
|
|
|
||
|
|
# Ruby tries to be helpful and adds new lines every 60 bytes :(
|
||
|
|
'ssh-rsa ' + [pack_pubkey_components(components)].pack('m').delete("\n")
|
||
|
|
end
|
||
|
|
|
||
|
|
private
|
||
|
|
|
||
|
|
# Encodes an openssh-mpi-encoded integer.
|
||
|
|
def encode_mpi(n)
|
||
|
|
chars, n = [], n.to_i
|
||
|
|
chars << (n & 0xff) && n >>= 8 while n != 0
|
||
|
|
chars << 0 if chars.empty? || chars.last >= 0x80
|
||
|
|
chars.reverse.pack('C*')
|
||
|
|
end
|
||
|
|
|
||
|
|
# Packs string components into an openssh-encoded pubkey.
|
||
|
|
def pack_pubkey_components(strings)
|
||
|
|
(strings.map { |s| [s.length].pack('N') }).zip(strings).flatten.join
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|
||
|
|
end
|