Module: HrrRbSsh::Transport::KexAlgorithm::DiffieHellman

Includes:
Loggable, IvComputable
Included in:
DiffieHellmanGroup14Sha1, DiffieHellmanGroup14Sha256, DiffieHellmanGroup15Sha512, DiffieHellmanGroup16Sha512, DiffieHellmanGroup17Sha512, DiffieHellmanGroup18Sha512, DiffieHellmanGroup1Sha1
Defined in:
lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman.rb,
lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman/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.rb', line 52

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,
    :'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.rb', line 16

def initialize logger: nil
  self.logger = logger
  @dh = OpenSSL::PKey::DH.new
  if @dh.respond_to?(:set_pqg)
    @dh.set_pqg OpenSSL::BN.new(self.class::P, 16), nil, OpenSSL::BN.new(self.class::G)
  else
    @dh.p = OpenSSL::BN.new(self.class::P, 16)
    @dh.g = OpenSSL::BN.new(self.class::G)
  end
  @dh.generate_key!
  @public_key = @dh.pub_key.to_i
end

#receive_kexdh_init(payload) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman.rb', line 72

def receive_kexdh_init payload
  Message::SSH_MSG_KEXDH_INIT.new(logger: logger).decode payload
end

#receive_kexdh_reply(payload) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman.rb', line 96

def receive_kexdh_reply payload
  Message::SSH_MSG_KEXDH_REPLY.new(logger: logger).decode payload
end

#send_kexdh_init(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman.rb', line 87

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

#send_kexdh_reply(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman.rb', line 76

def send_kexdh_reply transport
  message = {
    :'message number'                                => Message::SSH_MSG_KEXDH_REPLY::VALUE,
    :'server public host key and certificates (K_S)' => @k_s,
    :'f'                                             => @f,
    :'signature of H'                                => sign(transport),
  }
  payload = Message::SSH_MSG_KEXDH_REPLY.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.rb', line 48

def shared_secret
  @shared_secret
end

#sign(transport) ⇒ Object 



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# File 'lib/hrr_rb_ssh/transport/kex_algorithm/diffie_hellman.rb', line 67

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.rb', line 29

def start transport
  case transport.mode
  when Mode::SERVER
    @k_s = transport.server_host_key_algorithm.server_public_host_key
    @f   = @public_key
    message = receive_kexdh_init transport.receive
    @e = message[:'e']
    @shared_secret = OpenSSL::BN.new(@dh.compute_key(OpenSSL::BN.new(@e)), 2).to_i
    send_kexdh_reply transport
  when Mode::CLIENT
    @e   = @public_key
    send_kexdh_init transport
    message = receive_kexdh_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