Added the ruby/base64_encode encoder (closes #172).

README.md

@@ -210,6 +210,7 @@ $ ronin-payloads encoders
   powershell/hex_encode
   python/base64_encode
   python/hex_encode
+  ruby/base64_encode
   shell/base64_encode
   shell/hex_encode
   shell/hex_escape

lib/ronin/payloads/encoders/builtin/ruby/base64_encode.rb

@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+#
+# ronin-payloads - A Ruby micro-framework for writing and running exploit
+# payloads.
+#
+# Copyright (c) 2007-2024 Hal Brodigan (postmodern.mod3 at gmail.com)
+#
+# ronin-payloads is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published
+# by the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# ronin-payloads is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with ronin-payloads.  If not, see <https://www.gnu.org/licenses/>.
+#
+
+require 'ronin/payloads/encoders/ruby_encoder'
+require 'ronin/support/encoding/base64'
+
+module Ronin
+  module Payloads
+    module Encoders
+      module Ruby
+        #
+        # Encodes the given Ruby code as a Base64 string, then decodes it
+        # using `Base64.decode64()`, and then evaluates the decoded Ruby code
+        # using `eval()`.
+        #
+        #    puts('PWNED') -> require 'base64'; eval(Base64.decode64("cHV0cygnUFdORUQnKQ=="))
+        #
+        # @since 0.3.0
+        #
+        class Base64Encode < RubyEncoder
+
+          register 'ruby/base64_encode'
+
+          summary 'Encodes Ruby as base64'
+
+          description <<~DESC
+            Encodes the given Ruby code as a Base64 string, then decodes it
+            using `Base64.decode64()`, and then evaluates the decoded Ruby
+            code using `eval()`.
+
+              puts('PWNED') -> require 'base64'; eval(Base64.decode64("cHV0cygnUFdORUQnKQ=="))
+
+          DESC
+
+          #
+          # Encodes Ruby code as Base64.
+          #
+          # @param [String] ruby
+          #   The Ruby code to encode.
+          #
+          # @return [String]
+          #
+          def encode(ruby)
+            base64 = Support::Encoding::Base64.encode(ruby, mode: :strict)
+
+            %{require 'base64'; eval(Base64.decode64("#{base64}"))}
+          end
+
+        end
+      end
+    end
+  end
+end

spec/encoders/builtin/ruby/base64_encode_spec.rb

@@ -0,0 +1,17 @@
+require 'spec_helper'
+require 'ronin/payloads/encoders/builtin/ruby/base64_encode'
+
+describe Ronin::Payloads::Encoders::Ruby::Base64Encode do
+  it "must inherit from Ronin::Payloads::Encoders::RubyEncoder" do
+    expect(described_class).to be < Ronin::Payloads::Encoders::RubyEncoder
+  end
+
+  describe "#encode" do
+    let(:ruby)    { "puts('PWNED')" }
+    let(:encoded) { %{require 'base64'; eval(Base64.decode64("cHV0cygnUFdORUQnKQ=="))} }
+
+    it "must encode the given Ruby code as a Base64 string and embed it into the 'require 'base64'; eval(Base64.decode64(\"...\"))'" do
+      expect(subject.encode(ruby)).to eq(encoded)
+    end
+  end
+end