Module: HrrRbSsh::Transport::KexAlgorithm::DiffieHellmanGroupExchange

Includes:
Loggable, IvComputable
Included in:
DiffieHellmanGroupExchangeSha1, DiffieHellmanGroupExchangeSha256
Defined in:
lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb,
lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange/h0.rb

Defined Under Namespace

Classes: H0

Instance Attribute Summary

Attributes included from Loggable

#log_key, #logger

Instance Method Summary collapse

Methods included from IvComputable

#build_key, #iv_c_to_s, #iv_s_to_c, #key_c_to_s, #key_s_to_c, #mac_c_to_s, #mac_s_to_c

Methods included from Loggable

#log_debug, #log_error, #log_fatal, #log_info, #log_warn

Instance Method Details

#hash(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 79

def hash transport
  h0_payload = {
    :'V_C' => transport.v_c,
    :'V_S' => transport.v_s,
    :'I_C' => transport.i_c,
    :'I_S' => transport.i_s,
    :'K_S' => @k_s,
    :'min' => @min,
    :'n'   => @n,
    :'max' => @max,
    :'p'   => @p,
    :'g'   => @g,
    :'e'   => @e,
    :'f'   => @f,
    :'k'   => @shared_secret,
  }
  h0 = H0.new(logger: logger).encode h0_payload
  h = OpenSSL::Digest.digest self.class::DIGEST, h0
end

#initialize(logger: nil) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 16

def initialize logger: nil
  self.logger = logger
end

#initialize_dh(pg = nil) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 55

def initialize_dh pg=nil
  unless pg
    p_list = KexAlgorithm.list_supported.map{ |e| KexAlgorithm[e] }.select{ |e| e.const_defined?(:P) }.map{ |e| [OpenSSL::BN.new(e::P,16).num_bits, e::P] }.sort_by{ |e| e[0] }.reverse
    candidate = p_list.find{ |e| e[0] <= @n }
    raise unless (@min .. @max).include?(candidate[0])
    p, g = candidate[1], 2
  else
    p, g = pg
  end
  @dh = OpenSSL::PKey::DH.new
  if @dh.respond_to?(:set_pqg)
    @dh.set_pqg OpenSSL::BN.new(p, 16), nil, OpenSSL::BN.new(g)
  else
    @dh.p = OpenSSL::BN.new(p, 16)
    @dh.g = OpenSSL::BN.new(g)
  end
  @dh.generate_key!
  @public_key = @dh.pub_key.to_i
end

#receive_kex_dh_gex_group(payload) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 144

def receive_kex_dh_gex_group payload
  Message::SSH_MSG_KEX_DH_GEX_GROUP.new(logger: logger).decode payload
end

#receive_kex_dh_gex_init(payload) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 118

def receive_kex_dh_gex_init payload
  Message::SSH_MSG_KEX_DH_GEX_INIT.new(logger: logger).decode payload
end

#receive_kex_dh_gex_reply(payload) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 157

def receive_kex_dh_gex_reply payload
  Message::SSH_MSG_KEX_DH_GEX_REPLY.new(logger: logger).decode payload
end

#receive_kex_dh_gex_request(payload) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 104

def receive_kex_dh_gex_request payload
  Message::SSH_MSG_KEX_DH_GEX_REQUEST.new(logger: logger).decode payload
end

#send_kex_dh_gex_group(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 108

def send_kex_dh_gex_group transport
  message = {
    :'message number' => Message::SSH_MSG_KEX_DH_GEX_GROUP::VALUE,
    :'p'              => @p,
    :'g'              => @g,
  }
  payload = Message::SSH_MSG_KEX_DH_GEX_GROUP.new(logger: logger).encode message
  transport.send payload
end

#send_kex_dh_gex_init(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 148

def send_kex_dh_gex_init transport
  message = {
    :'message number' => Message::SSH_MSG_KEX_DH_GEX_INIT::VALUE,
    :'e'              => @e,
  }
  payload = Message::SSH_MSG_KEX_DH_GEX_INIT.new(logger: logger).encode message
  transport.send payload
end

#send_kex_dh_gex_reply(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 122

def send_kex_dh_gex_reply transport
  message = {
    :'message number'                                => Message::SSH_MSG_KEX_DH_GEX_REPLY::VALUE,
    :'server public host key and certificates (K_S)' => @k_s,
    :'f'                                             => @f,
    :'signature of H'                                => sign(transport),
  }
  payload = Message::SSH_MSG_KEX_DH_GEX_REPLY.new(logger: logger).encode message
  transport.send payload
end

#send_kex_dh_gex_request(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 133

def send_kex_dh_gex_request transport
  message = {
    :'message number' => Message::SSH_MSG_KEX_DH_GEX_REQUEST::VALUE,
    :'min'            => @min,
    :'n'              => @n,
    :'max'            => @max,
  }
  payload = Message::SSH_MSG_KEX_DH_GEX_REQUEST.new(logger: logger).encode message
  transport.send payload
end

#shared_secret ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 75

def shared_secret
  @shared_secret
end

#sign(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 99

def sign transport
  h = hash transport
  s = transport.server_host_key_algorithm.sign h
end

#start(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman_group_exchange.rb', line 20

def start transport
  case transport.mode
  when Mode::SERVER
    message = receive_kex_dh_gex_request transport.receive
    @min = message[:'min']
    @n   = message[:'n']
    @max = message[:'max']
    initialize_dh
    @p = @dh.p.to_i
    @g = @dh.g.to_i
    send_kex_dh_gex_group transport
    @k_s = transport.server_host_key_algorithm.server_public_host_key
    @f   = @public_key
    message = receive_kex_dh_gex_init transport.receive
    @e   = message[:'e']
    @shared_secret = OpenSSL::BN.new(@dh.compute_key(OpenSSL::BN.new(@e)), 2).to_i
    send_kex_dh_gex_reply transport
  when Mode::CLIENT
    @min = 1024
    @n   = 2048
    @max = 8192
    send_kex_dh_gex_request transport
    message = receive_kex_dh_gex_group transport.receive
    @p   = message[:'p']
    @g   = message[:'g']
    initialize_dh [@p, @g]
    @e   = @public_key
    send_kex_dh_gex_init transport
    message = receive_kex_dh_gex_reply transport.receive
    @k_s = message[:'server public host key and certificates (K_S)']
    @f   = message[:'f']
    @shared_secret = OpenSSL::BN.new(@dh.compute_key(OpenSSL::BN.new(@f)), 2).to_i
  end
end