apdu refactoring plus tests

examples/listen.rb

@@ -5,40 +5,34 @@
 puts "Available readers: %s" % readers.to_s
 
 # The order of tag types in poll arguments defines priority of tag types
-readers[0].poll(IsoDep::Tag, Mifare::Classic::Tag, Mifare::Ultralight::Tag, NFC::Tag) do |tag|
+readers[0].poll(IsoDep::Tag, Mifare::Classic::Tag, Mifare::Ultralight::Tag) do |tag|
  begin
  puts "Applied #{tag.class.name}: #{tag}"
 
  case tag
  when Mifare::Classic::Tag
- tag.select do
- # Perform authentication to block 0x04 with the Key A that equals 
- # to "\xFF\xFF\xFF\xFF\xFF\xFF" you can also use "FFFFFFFFFFFF"
- # representation. In this case it will be automatically packed to 6 bytes
- if auth(4, :key_a, "FFFFFFFFFFFF")
- puts "authenticated!"
- processed! # mark tag as processed so even if it supports different
- # protocol poll method will continue with another physical
- # tag
- end
- end
+ # Perform authentication to block 0x04 with the Key A that equals 
+ # to "\xFF\xFF\xFF\xFF\xFF\xFF" you can also use "FFFFFFFFFFFF"
+ # representation. In this case it will be automatically packed to 6 bytes
+ if auth(4, :key_a, "FFFFFFFFFFFF")
+ puts "authenticated!"
+ processed! # mark tag as processed so even if it supports different
+ # protocol poll method will continue with another physical
+ # tag
+ end
  when Mifare::Ultralight::Tag
- tag.select do
- puts "Page 1: %s" % read(1).unpack('H*').pop
- processed!
- end
+ puts "Page 1: %s" % read(1).unpack('H*').pop
+ processed!
  when IsoDep::Tag
- aid = ["F75246544101"].pack('H*')
- tag.select(aid) do
- # sending APDU command to tag using send_apdu method
- apdu = ['A00D010018B455CAF0F331AF703EFA2E2D744EC7E22AA64076CD19F6D0'].pack('H*')
- puts send_apdu(apdu).unpack('H*').pop
+ select ["F75246544101"].pack('H*')
+ # sending APDU command to tag using send_apdu method
+ apdu = ['A00D010018B455CAF0F331AF703EFA2E2D744EC7E22AA64076CD19F6D0'].pack('H*')
+ puts send_apdu(apdu).unpack('H*').pop
 
- # sending APDU command with "<<" operator which is alias to send_apdu
- # response = tag << apdu
- # puts response.unpack('H*').pop
- processed!
- end
+ # sending APDU command with "<<" operator which is alias to send_apdu
+ # response = tag << apdu
+ # puts response.unpack('H*').pop
+ processed!
  end
  rescue Exception => e
  puts e

lib/ruby-nfc/apdu/response.rb

@@ -1,20 +1,20 @@
+require_relative './apdu'
+
 module APDU
  class Response
  def initialize(response)
- @response = response
- end
+ resp_8bit = response.dup
+  resp_8bit.force_encoding('ASCII-8BIT')
 
- # Public: Parse response without checking SW
- def parse
+ raise APDU::Error, "Response must be at least 2-bytes long" if resp_8bit.size < 2
 
+ @response = resp_8bit
  end
 
- # Public: Parse APDU response and check SW after. 
- #
- # Returns instance of APDU::Response class
- # Raises APDU::Errno if SW != 9000
- def parse!
-
+ # Public: Raises APDU::Errno if self.sw is not equal 0x9000
+ def raise_errno!
+ raise APDU::Errno.new(sw) if sw != 0x9000
+ self
  end
 
  # Public: Return Status Word of an APDU response. Status Word is a two-byte
@@ -23,12 +23,12 @@ def sw
  @response[-2, 2].unpack('n').pop
  end
 
- # Public: Return high byte of Status Word aka SW1
+ # Public: Return high byte of Status Word
  def sw1
  @response[-2, 1].unpack('C').pop
  end
 
- # Public: Return low byte of Status Word aka SW2
+ # Public: Return low byte of Status Word
  def sw2
  @response[-1,1].unpack('C').pop
  end

lib/ruby-nfc/reader.rb

@@ -26,7 +26,7 @@ def discover(*card_types)
  end
  end
 
- def poll(*card_types)
+ def poll(*card_types, &block)
  connect
 
  LibNFC.nfc_initiator_init(@ptr) # we'll be initiator not a target
@@ -57,7 +57,7 @@ def poll(*card_types)
  card_types.each do |card_type|
  if card_type.match?(target)
  tag = card_type.new(target, self)
- yield tag
+ tag.connect(&block)
  # if this tag was marked as processed - continue with next tag
  break if target.processed?
  end

lib/ruby-nfc/tags/isodep.rb

@@ -1,5 +1,7 @@
 require_relative '../nfc'
 require_relative './tag'
+require_relative '../apdu/request'
+require_relative '../apdu/response'
 
 module IsoDep
  ISO_14443_4_COMPATIBLE = 0x20
@@ -12,7 +14,7 @@ def self.match?(target)
  target[:nti][:nai][:btSak] & IsoDep::ISO_14443_4_COMPATIBLE > 0
  end
 
- def select(aid = nil, &block)
+ def connect(&block)
  @reader.set_flag(:NP_AUTO_ISO14443_4, true)
 
  modulation = LibNFC::Modulation.new
@@ -45,10 +47,28 @@ def select(aid = nil, &block)
  end
  end
 
- def deselect
+ def disconnect
  0 == LibNFC.nfc_initiator_deselect_target(@reader.ptr)
  end
 
+ # Public: Select application with given AID (Application Identifier)
+ # 
+ # aid - Application Identifier of an applet located on a card
+ #
+ # Returns nothing.
+ # Raises APDU::Errno if application with such AID doesn't exists on a card
+ def select(aid)
+ send_apdu!("\x00\xA4\x04\x00#{aid.size.chr}#{aid}")
+ end
+
+ # Public: Send APDU command to tag
+ #
+ # apdu - APDU command to send. see ISO/IEC 7816-4 or wiki for details.
+ # APDU is a binary string that should 
+ # 
+ #
+ # Returns APDU::Response object
+ # Raises IsoDep::Error if card didn't respond
  def send_apdu(apdu)
  cmd = apdu
  cmd.force_encoding('ASCII-8BIT')
@@ -62,7 +82,18 @@ def send_apdu(apdu)
 
  raise IsoDep::Error, "APDU sending failed: #{res_len}" if res_len < 0
 
- response_buffer.get_bytes(0, res_len).to_s
+ APDU::Response.from_string(response_buffer.get_bytes(0, res_len).to_s)
+ end
+
+ # Public: Send APDU command to tag and raises APDU::Errno exception
+ # if SW not equal to 0x9000
+ # 
+ # apdu - APDU command to transmit to the tag
+ #
+ # Returns APDU::Response object
+ # Raises APDU::Errno if SW is not equal to 0x9000 
+ def send_apdu!(apdu)
+ send_apdu(apdu).raise_errno!
  end
 
  alias :'<<' :send_apdu

lib/ruby-nfc/tags/mifare/classic.rb

@@ -40,18 +40,18 @@ def initialize(target, reader)
  @auth_block = nil #last authenticated block
  end
 
- def select(&block)
+ def connect(&block)
  @reader.set_flag(:NP_AUTO_ISO14443_4, false)
 
  res = Mifare.mifare_classic_connect(@pointer)
  if 0 == res 
  super
  else
- raise Mifare::Error, "Can't select tag: #{res}"
+ raise Mifare::Error, "Can't connect tag: #{res}"
  end
  end
 
- def deselect
+ def disconnect
  Mifare.mifare_classic_disconnect(@pointer)
  super
  end

lib/ruby-nfc/tags/mifare/tag.rb

@@ -51,7 +51,7 @@ def to_s
  end
 
  # frees memory allocated for mifare tag
- def deselect
+ def disconnect
  Mifare.freefare_free_tag(@pointer)
  end
 

lib/ruby-nfc/tags/mifare/ultralight.rb

@@ -14,18 +14,18 @@ module Mifare
 
  module Ultralight
  class Tag < Mifare::Tag
- def select(&block)
+ def connect(&block)
  @reader.set_flag(:NP_AUTO_ISO14443_4, false)
 
  res = Mifare.mifare_ultralight_connect(@pointer)
  if 0 == res 
  super
  else
- raise Mifare::Error, "Can't select tag: #{res}"
+ raise Mifare::Error, "Can't connect to tag: #{res}"
  end
  end
 
- def deselect
+ def disconnect
  Mifare.mifare_ultralight_disconnect(@pointer)
  super
  end

lib/ruby-nfc/tags/tag.rb

@@ -6,12 +6,12 @@ def initialize(target, reader)
  @processed = false
  end
 
- def select(&block)
+ def connect(&block)
  if block_given?
  begin
  self.instance_eval(&block)
  ensure
- deselect
+ disconnect
  end
  end
  end
@@ -24,6 +24,8 @@ def processed?
  @target.processed?
  end
 
+ def disconnect; end
+
  def uid
  uid_size = @target[:nti][:nai][:szUidLen]
  @target[:nti][:nai][:abtUid].to_s[0...uid_size]

ruby-nfc.gemspec

@@ -21,7 +21,10 @@ Gem::Specification.new do |s|
  "./lib/ruby-nfc/tags/isodep.rb",
  "./lib/ruby-nfc/tags/tag.rb",
  "./lib/ruby-nfc/reader.rb",
- "./lib/ruby-nfc/libnfc.rb"
+ "./lib/ruby-nfc/libnfc.rb",
+ "./lib/ruby-nfc/apdu/apdu.rb",
+ "./lib/ruby-nfc/apdu/request.rb",
+ "./lib/ruby-nfc/apdu/response.rb"
  ]
 
  s.homepage = 'https://github.com/maximchick/ruby-nfc'

test/apdu_request_test.rb

@@ -1,7 +1,7 @@
 require 'test_helper'
 require 'ruby-nfc/apdu/request'
 
-class PostTest < MiniTest::Unit::TestCase
+class APDURequestTest < MiniTest::Unit::TestCase
  def test_raise_apdu_error_if_length_too_small
  e = assert_raises(APDU::Error) {APDU::Request.from_string("123")}
  assert_match e.message, /too short/

test/apdu_response_test.rb

@@ -0,0 +1,34 @@
+require 'test_helper'
+require 'ruby-nfc/apdu/response'
+
+class APDUResponseTest < MiniTest::Unit::TestCase
+ def setup
+ @response = APDU::Response.new("\x01\x02\x03\x04\x69\x85")
+ end
+
+ def test_raise_apdu_error_if_length_too_small
+ assert_raises(APDU::Error) { APDU::Response.new("") }
+ end
+
+ def test_data
+ assert_equal "\x01\x02\x03\x04", @response.data
+ end
+
+ def test_sw
+ assert_equal 0x6985, @response.sw
+ end
+
+ def test_sw1
+ assert_equal 0x69, @response.sw1
+ end
+
+ def test_sw2
+ assert_equal 0x85, @response.sw2
+ end
+
+ def test_raise_errno
+ e = assert_raises(APDU::Errno) { @response.raise_errno! }
+ assert_equal 0x6985, e.code
+ end
+
+end