serve: Make some error conditions non-fatal, test them.

We don't want flexnbd serve to fall over and die if the client sends an invalid request.

tests/acceptance/fakes/source/connect_from_banned_ip.rb

@@ -13,10 +13,8 @@ addr, port = *ARGV
 
 client = FakeSource.new( addr, port, "Timed out connecting", "127.0.0.6" )
 sleep( 0.25 )
-client.ensure_disconnected
 
+rsp = client.disconnected? ? 0 : 1
 client.close
-exit(0)
-
-
+exit(rsp)
 

tests/acceptance/file_writer.rb

@@ -8,6 +8,10 @@ class FileWriter
     @pattern = ""
   end
 
+  def size
+    @blocksize * @pattern.split("").size
+  end
+
   # We write in fixed block sizes, given by "blocksize"
   #    _ means skip a block
   #    0 means write a block full of zeroes

tests/acceptance/flexnbd/constants.rb

@@ -32,6 +32,9 @@ module FlexNBD
   end
 
   read_constants()
+
+  REQUEST_MAGIC = "\x25\x60\x95\x13" unless defined?(REQUEST_MAGIC)
+  REPLY_MAGIC = "\x67\x44\x66\x98" unless defined?(REPLY_MAGIC)
+
 end # module FlexNBD
 
-

tests/acceptance/flexnbd/fake_dest.rb

@@ -56,8 +56,6 @@ module FlexNBD
         }
       end
 
-      REPLY_MAGIC="\x67\x44\x66\x98"
-
       def write_error( handle )
         write_reply( handle, 1 )
       end
@@ -76,7 +74,7 @@ module FlexNBD
         if opts[:magic] == :wrong
           write_rand( @sock, 4 )
         else
-          @sock.write( REPLY_MAGIC )
+          @sock.write( ::FlexNBD::REPLY_MAGIC )
         end
 
         @sock.write( [err].pack("N") )
@@ -93,6 +91,10 @@ module FlexNBD
         @sock.read( len )
       end
 
+      def write_data( len )
+        @sock.write( len )
+      end
+
 
       def self.parse_be64(str)
         raise "String is the wrong length: 8 bytes expected (#{str.length} received)" unless
@@ -161,3 +163,4 @@ module FlexNBD
 
   end # module FakeDest
 end # module FlexNBD
+

tests/acceptance/flexnbd/fake_source.rb

@@ -30,7 +30,7 @@ module FlexNBD
 
 
     def read_hello()
-      timing_out( FlexNBD::MS_HELLO_TIME_SECS,
+      timing_out( ::FlexNBD::MS_HELLO_TIME_SECS,
                   "Timed out waiting for hello." ) do
         fail "No hello." unless (hello = @sock.read( 152 )) &&
           hello.length==152
@@ -47,15 +47,14 @@ module FlexNBD
     end
 
 
-    def send_request( type, handle="myhandle", from=0, len=0 )
+    def send_request( type, handle="myhandle", from=0, len=0, magic=REQUEST_MAGIC )
       fail "Bad handle" unless handle.length == 8
 
-      @sock.write( "\x25\x60\x95\x13" )
+      @sock.write( magic )
       @sock.write( [type].pack( 'N' ) )
       @sock.write( handle )
-      @sock.write( "\x0"*4 )
-      @sock.write( [from].pack( 'N' ) )
-      @sock.write( [len ].pack( 'N' ) )
+      @sock.write( [n64( from )].pack( 'q' ) )
+      @sock.write( [len].pack( 'N' ) )
     end
 
 
@@ -122,10 +121,10 @@ module FlexNBD
     end
 
 
-    def ensure_disconnected
-      Timeout.timeout( 2 ) do
-        @sock.read(1)
-      end
+    def disconnected?
+      result = nil
+      Timeout.timeout( 2 ) { result = ( @sock.read(1) == nil ) }
+      result
     end
 
 
@@ -140,6 +139,22 @@ module FlexNBD
       end
     end
 
+    private
+
+    # take a 64-bit number, turn it upside down (due to :
+    #   http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-core/11920
+    # )
+    def n64(b)
+      ((b & 0xff00000000000000) >> 56) |
+      ((b & 0x00ff000000000000) >> 40) |
+      ((b & 0x0000ff0000000000) >> 24) |
+      ((b & 0x000000ff00000000) >> 8)  |
+      ((b & 0x00000000ff000000) << 8)  |
+      ((b & 0x0000000000ff0000) << 24) |
+      ((b & 0x000000000000ff00) << 40) |
+      ((b & 0x00000000000000ff) << 56)
+    end
 
   end # class FakeSource
 end # module FlexNBD
+

tests/acceptance/test_serve_mode.rb

@@ -0,0 +1,86 @@
+require 'test/unit'
+require 'environment'
+require 'flexnbd/fake_source'
+
+class TestServeMode < Test::Unit::TestCase
+
+  def setup
+    super
+    @env = Environment.new
+    @env.writefile1( "0" )
+    @env.serve1
+  end
+
+  def teardown
+    @env.cleanup
+    super
+  end
+
+  def connect_to_server
+    client = FlexNBD::FakeSource.new(@env.ip, @env.port1, "Connecting to server failed")
+    begin
+      result = client.read_hello
+      assert_equal "NBDMAGIC", result[:magic]
+      assert_equal @env.file1.size, result[:size]
+      yield client
+    ensure
+      client.close rescue nil
+    end
+  end
+
+  def test_bad_request_magic_receives_error_response
+    connect_to_server do |client|
+
+      # replace REQUEST_MAGIC with all 0s to make it look bad
+      client.send_request( 0, "myhandle", 0, 0, "\x00\x00\x00\x00" )
+      rsp = client.read_response
+
+      assert_equal FlexNBD::REPLY_MAGIC, rsp[:magic]
+      assert_equal "myhandle", rsp[:handle]
+      assert rsp[:error] != 0, "Server sent success reply back: #{rsp[:error]}"
+
+      # The client should be disconnected now
+      assert client.disconnected?, "Server not disconnected"
+    end
+  end
+
+
+  def test_read_request_out_of_bounds_receives_error_response
+    connect_to_server do |client|
+      client.write_read_request( @env.file1.size, 4096 )
+      rsp = client.read_response
+
+      assert_equal FlexNBD::REPLY_MAGIC, rsp[:magic]
+      assert_equal "myhandle", rsp[:handle]
+      assert rsp[:error] != 0, "Server sent success reply back: #{rsp[:error]}"
+
+      # Ensure we're not disconnected by sending a request. We don't care about
+      # whether the reply is good or not, here.
+      client.write_read_request( 0, 4096 )
+      rsp = client.read_response
+      assert_equal FlexNBD::REPLY_MAGIC, rsp[:magic]
+    end
+  end
+
+  def test_write_request_out_of_bounds_receives_error_response
+    connect_to_server do |client|
+      client.write( @env.file1.size, "\x00" * 4096 )
+      rsp = client.read_response
+
+      assert_equal FlexNBD::REPLY_MAGIC, rsp[:magic]
+      assert_equal "myhandle", rsp[:handle]
+      assert rsp[:error] != 0, "Server sent success reply back: #{rsp[:error]}"
+
+      # Ensure we're not disconnected by sending a request. We don't care about
+      # whether the reply is good or not, here.
+      client.write( 0, "\x00" * @env.file1.size )
+      rsp = client.read_response
+      assert_equal FlexNBD::REPLY_MAGIC, rsp[:magic]
+    end
+
+  end
+
+
+
+end
+