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require 'openssl'
require 'ostruct'
require_relative '../../common'
require_relative './test_diffie_hellman_group1_sha1'
require 'net/ssh/transport/kex/ecdh_sha2_nistp256'
module Transport
module Kex
class TestEcdhSHA2NistP256 < NetSSHTest
include Net::SSH::Transport::Constants
def setup
@ecdh = @algorithms = @connection = @server_key =
@packet_data = @shared_secret = nil
end
def test_exchange_keys_should_return_expected_results_when_successful
result = exchange!
assert_equal session_id, result[:session_id]
assert_equal server_host_key.to_blob, result[:server_key].to_blob
assert_equal shared_secret, result[:shared_secret]
assert_equal digester, result[:hashing_algorithm]
end
def test_exchange_keys_with_unverifiable_host_should_raise_exception
connection.verifier { false }
assert_raises(Net::SSH::Exception) { exchange! }
end
def test_exchange_keys_with_signature_key_type_mismatch_should_raise_exception
assert_raises(Net::SSH::Exception) { exchange! key_type: 'ssh-dss' }
end
def test_exchange_keys_with_host_key_type_mismatch_should_raise_exception
algorithms host_key: 'ssh-dss'
assert_raises(Net::SSH::Exception) { exchange! key_type: 'ssh-dss' }
end
def test_exchange_keys_when_server_signature_could_not_be_verified_should_raise_exception
@signature = '1234567890'
assert_raises(Net::SSH::Exception) { exchange! }
end
def test_exchange_keys_should_pass_expected_parameters_to_host_key_verifier
verified = false
connection.verifier do |data|
verified = true
assert_equal server_host_key.to_blob, data[:key].to_blob
blob = b(:key, data[:key]).to_s
fingerprint = "SHA256:#{Base64.encode64(OpenSSL::Digest.digest('SHA256', blob)).chomp.gsub(/=+\z/, '')}"
assert_equal blob, data[:key_blob]
assert_equal fingerprint, data[:fingerprint]
assert_equal connection, data[:session]
true
end
assert_nothing_raised { exchange! }
assert verified
end
private
def digester
OpenSSL::Digest::SHA256
end
def subject
Net::SSH::Transport::Kex::EcdhSHA2NistP256
end
def ecparam
'prime256v1'
end
def key_type
'ecdsa-sha2-nistp256'
end
def exchange!(options = {})
connection.expect do |t, buffer|
assert_equal KEXECDH_INIT, buffer.type
assert_equal ecdh.ecdh.public_key.to_bn.to_s(2), buffer.read_string
t.return(KEXECDH_REPLY,
:string, b(:key, server_host_key),
:string, server_ecdh_pubkey.to_bn.to_s(2),
:string, b(:string, options[:key_type] || key_type,
:string, signature))
connection.expect do |t2, buffer2|
assert_equal NEWKEYS, buffer2.type
t2.return(NEWKEYS)
end
end
ecdh.exchange_keys
end
def ecdh
@ecdh ||= subject.new(algorithms, connection, packet_data)
end
def algorithms(options = {})
@algorithms ||= OpenStruct.new(host_key: options[:server_host_key] || 'ecdsa-sha2-nistp256', host_key_format: options[:server_host_key] || 'ecdsa-sha2-nistp256')
end
def connection
@connection ||= MockTransport.new
end
def server_key
@server_key ||= OpenSSL::PKey::EC.new(ecparam).generate_key
end
def server_host_key
@server_host_key ||= OpenSSL::PKey::EC.new('prime256v1').generate_key
end
def packet_data
@packet_data ||= { client_version_string: 'client version string',
server_version_string: 'server version string',
server_algorithm_packet: 'server algorithm packet',
client_algorithm_packet: 'client algorithm packet' }
end
def server_ecdh_pubkey
@server_ecdh_pubkey ||= server_key.public_key
end
def shared_secret
@shared_secret ||= OpenSSL::BN.new(ecdh.ecdh.dh_compute_key(server_ecdh_pubkey), 2)
end
def session_id
@session_id ||= begin
buffer = Net::SSH::Buffer.from(:string, packet_data[:client_version_string],
:string, packet_data[:server_version_string],
:string, packet_data[:client_algorithm_packet],
:string, packet_data[:server_algorithm_packet],
:string, Net::SSH::Buffer.from(:key, server_host_key),
:string, ecdh.ecdh.public_key.to_bn.to_s(2),
:string, server_ecdh_pubkey.to_bn.to_s(2),
:bignum, shared_secret)
digester.digest(buffer.to_s)
end
end
def signature
@signature ||= server_host_key.ssh_do_sign(session_id)
end
def b(*args)
Net::SSH::Buffer.from(*args)
end
end
end
end
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