Land #5570, @todb-r7 Removes references to Iconv gem, since it's deprecated

lib/rex/text.rb

@@ -4,17 +4,7 @@ require 'digest/sha1'
 require 'stringio'
 require 'cgi'
 require 'rex/powershell'
-
-%W{ iconv zlib }.each do |libname|
-  begin
-    old_verbose = $VERBOSE
-    $VERBOSE = nil
-    require libname
-  rescue ::LoadError
-  ensure
-    $VERBOSE = old_verbose
-  end
-end
+require 'zlib'
 
 module Rex
 
@@ -55,7 +45,8 @@ module Text
 
   DefaultPatternSets = [ Rex::Text::UpperAlpha, Rex::Text::LowerAlpha, Rex::Text::Numerals ]
 
-  # In case Iconv isn't loaded
+  # The Iconv translation table. The Iconv gem is deprecated in favor of
+  # String#encode, yet there is no encoding for EBCDIC. See #4525
   Iconv_EBCDIC = [
     "\x00", "\x01", "\x02", "\x03", "7", "-", ".", "/", "\x16", "\x05",
     "%", "\v", "\f", "\r", "\x0E", "\x0F", "\x10", "\x11", "\x12", "\x13",
@@ -374,31 +365,26 @@ module Text
     return str
   end
 
+  # Converts US-ASCII to UTF-8, skipping over any characters which don't
+  # convert cleanly. This is a convenience method that wraps
+  # String#encode with non-raising default paramaters.
   #
-  # Converts ISO-8859-1 to UTF-8
-  #
+  # @param str [String] An encodable ASCII string
+  # @return [String] a UTF-8 equivalent
+  # @note This method will discard invalid characters
   def self.to_utf8(str)
-
-    if str.respond_to?(:encode)
-      # Skip over any bytes that fail to convert to UTF-8
-      return str.encode('utf-8', { :invalid => :replace, :undef => :replace, :replace => '' })
+      str.encode('utf-8', { :invalid => :replace, :undef => :replace, :replace => '' })
   end
 
-    begin
-      Iconv.iconv("utf-8","iso-8859-1", str).join(" ")
-    rescue
-      raise ::RuntimeError, "Your installation does not support iconv (needed for utf8 conversion)"
-    end
-  end
-
-  #
-  # Converts ASCII to EBCDIC
-  #
   class IllegalSequence < ArgumentError; end
 
-  # A native implementation of the ASCII->EBCDIC table, used to fall back from using
-  # Iconv
-  def self.to_ebcdic_rex(str)
+  # A native implementation of the ASCII to EBCDIC conversion table, since
+  # EBCDIC isn't available to String#encode as of Ruby 2.1
+  #
+  # @param str [String] An encodable ASCII string
+  # @return [String] an EBCDIC encoded string
+  # @note This method will raise in the event of invalid characters
+  def self.to_ebcdic(str)
     new_str = []
     str.each_byte do |x|
       if Iconv_ASCII.index(x.chr)
@@ -410,9 +396,13 @@ module Text
     new_str.join
   end
 
-  # A native implementation of the EBCDIC->ASCII table, used to fall back from using
-  # Iconv
-  def self.from_ebcdic_rex(str)
+  # A native implementation of the EBCIDC to ASCII conversion table, since
+  # EBCDIC isn't available to String#encode as of Ruby 2.1
+  #
+  # @param str [String] an EBCDIC encoded string
+  # @return [String] An encodable ASCII string
+  # @note This method will raise in the event of invalid characters
+  def self.from_ebcdic(str)
     new_str = []
     str.each_byte do |x|
       if Iconv_EBCDIC.index(x.chr)
@@ -424,29 +414,6 @@ module Text
     new_str.join
   end
 
-  def self.to_ebcdic(str)
-    begin
-      Iconv.iconv("EBCDIC-US", "ASCII", str).first
-    rescue ::Iconv::IllegalSequence => e
-      raise e
-    rescue
-      self.to_ebcdic_rex(str)
-    end
-  end
-
-  #
-  # Converts EBCIDC to ASCII
-  #
-  def self.from_ebcdic(str)
-    begin
-      Iconv.iconv("ASCII", "EBCDIC-US", str).first
-    rescue ::Iconv::IllegalSequence => e
-      raise e
-    rescue
-      self.from_ebcdic_rex(str)
-    end
-  end
-
   #
   # Returns the words in +str+ as an Array.
   #

spec/lib/rex/text_spec.rb

@@ -4,6 +4,31 @@ require 'rex/text'
 describe Rex::Text do
   context "Class methods" do
 
+    context ".to_ebcdic" do
+      it "should convert ASCII to EBCDIC (both US standards)" do
+        described_class.to_ebcdic("Hello, World!").should eq("\xc8\x85\x93\x93\x96\x6b\x40\xe6\x96\x99\x93\x84\x5a")
+      end
+      it "should raise on non-convertable characters" do
+        lambda {described_class.to_ebcdic("\xff\xfe")}.should raise_exception(described_class::IllegalSequence)
+      end
+    end
+
+    context ".from_ebcdic" do
+      it "should convert EBCDIC to ASCII (both US standards)" do
+        described_class.from_ebcdic("\xc8\x85\x93\x93\x96\x6b\x40\xe6\x96\x99\x93\x84\x5a").should eq("Hello, World!")
+      end
+      it "should raise on non-convertable characters" do
+        lambda {described_class.from_ebcdic("\xff\xfe")}.should raise_exception(described_class::IllegalSequence)
+      end
+    end
+
+    context ".to_utf8" do
+      it "should convert a string to UTF-8, skipping badchars" do
+        described_class.to_utf8("Hello, world!").should eq("Hello, world!")
+        described_class.to_utf8("Oh no, \xff\xfe can't convert!").should eq("Oh no,  can't convert!")
+      end
+    end
+
     context ".to_octal" do
       it "should convert all chars 00 through ff" do
         described_class.to_octal("\x7f"*100).should eq("\\177"*100)