Adds Rubocop rule to detect leading/trailing whitespace in module metadata

.rubocop.yml

@@ -23,6 +23,7 @@ require:
   - ./lib/rubocop/cop/lint/deprecated_gem_version.rb
   - ./lib/rubocop/cop/lint/module_enforce_notes.rb
   - ./lib/rubocop/cop/lint/detect_invalid_pack_directives.rb
+  - ./lib/rubocop/cop/lint/detect_metadata_trailing_leading_whitespace.rb
 
 Layout/SpaceBeforeBrackets:
   Enabled: true
@@ -672,3 +673,6 @@ Style/UnpackFirst:
     Disabling to make it easier to copy/paste `unpack('h*')` expressions from code
     into a debugging REPL.
   Enabled: false
+
+Lint/DetectMetadataTrailingLeadingWhitespace:
+  Enabled: true

lib/rubocop/cop/lint/detect_metadata_trailing_leading_whitespace.rb

@@ -0,0 +1,90 @@
+# frozen_string_literal: trueAdd commentMore actions
+
+module RuboCop
+  module Cop
+    module Lint
+      # Checks for leading or trailing whitespace in Metasploit module metadata keys/values
+      # inside the initialize method. Recursively checks all hash and array values, except for
+      # keys listed in EXEMPT_KEYS.
+      #
+      # EXEMPT_KEYS can be extended to skip additional metadata fields as needed.
+      #
+      # @example
+      #   # bad
+      #   'Name' => ' value '
+      #   'Author' => [' hd']
+      #
+      #   # good
+      #   'Name' => 'value'
+      #   'Author' => ['hd']
+      class DetectMetadataTrailingLeadingWhitespace < Base
+        extend AutoCorrector
+        MSG = 'Metadata key or value has leading or trailing whitespace.'
+        EXEMPT_KEYS = %w[Description Payload].freeze
+
+        # Called for every method definition node
+        # Only processes the initialize method
+        # @param node [RuboCop::AST::DefNode]
+        def on_def(node)
+          return unless node.method_name == :initialize
+
+          node.each_descendant(:hash) do |hash_node|
+            hash_node.pairs.each do |pair|
+              key = extract_string(pair.key)
+              next if key && EXEMPT_KEYS.any? { |exempt| key.casecmp?(exempt) }
+              check_value(pair.value)
+              if key && (key != key.strip)
+                add_offense(pair.key, message: MSG) do |corrector|
+                  corrector.replace(pair.key.loc.expression, key.strip.inspect)
+                end
+              end
+            end
+          end
+        end
+
+        private
+
+        # Recursively checks a value node for whitespace issues
+        # @param node [RuboCop::AST::Node]
+        def check_value(node)
+          case node.type
+          when :str, :dstr
+            value = extract_string(node)
+            if value && value != value.strip
+              add_offense(node, message: MSG) do |corrector|
+                replacement = node.sym_type? ? ":#{value.strip}" : value.strip.inspect
+                corrector.replace(node.loc.expression, replacement)
+              end
+            end
+          when :array
+            node.children.each { |child| check_value(child) }
+          when :hash
+            node.pairs.each do |pair|
+              key = extract_string(pair.key)
+              next if key && EXEMPT_KEYS.any? { |exempt| key.casecmp?(exempt) }
+              if key && key != key.strip
+                add_offense(pair.key, message: MSG) do |corrector|
+                  corrector.replace(pair.key.loc.expression, key.strip.inspect)
+                end
+              end
+              check_value(pair.value)
+            end
+          end
+        end
+
+        # Extracts the string value from a node (handles str, sym, dstr)
+        # @param node [RuboCop::AST::Node]
+        # @return [String, nil]
+        def extract_string(node)
+          return unless node
+          if node.str_type? || node.sym_type?
+            node.value.to_s
+          elsif node.dstr_type?
+            # For dynamic strings, join all child string values
+            node.children.map { |c| c.is_a?(Parser::AST::Node) ? extract_string(c) : c.to_s }.join
+          end
+        end
+      end
+    end
+  end
+end

spec/rubocop/cop/lint/detect_metadata_trailing_leading_whitespace_spec.rb

@@ -0,0 +1,131 @@
+# frozen_string_literal: trueAdd commentMore actions
+
+require 'rubocop/cop/lint/detect_metadata_trailing_leading_whitespace'
+require 'rubocop/rspec/support'
+
+RSpec.describe RuboCop::Cop::Lint::DetectMetadataTrailingLeadingWhitespace, :config do
+  subject(:cop) { described_class.new(config) }
+
+  let(:config) { RuboCop::Config.new }
+
+  it 'registers an offense for leading/trailing whitespace in Name' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'Name' => ' value ',
+                    ^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in Author (array)' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'Author' => [
+            ' author ',
+            ^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+          ],
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in License' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'License' => ' MSF_LICENSE ',
+                       ^^^^^^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in Privileged' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'Privileged' => ' true ',
+                          ^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in DefaultOptions (hash)' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'DefaultOptions' => {
+            'WfsDelay' => ' 10 ',
+                          ^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+          },
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in References (array of arrays)' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'References' => [
+            [ ' CVE ', ' 1999-0504 ' ],
+              ^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+                       ^^^^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+          ],
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in Platform' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'Platform' => ' win ',
+                        ^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in Targets (array of arrays)' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'Targets' => [
+            [ ' Automatic ', { 'Arch' => [ ' ARCH_X86 ', ' ARCH_X64 ' ] } ],
+              ^^^^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+                                                         ^^^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+                                           ^^^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+          ],
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in DefaultTarget' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'DefaultTarget' => ' 0 ',
+                             ^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+        ))
+      end
+    RUBY
+  end
+
+  it 'registers an offense for leading/trailing whitespace in DisclosureDate' do
+    expect_offense(<<~RUBY)
+      def initialize(info = {})
+        super(update_info(info,
+          'DisclosureDate' => ' 1999-01-01 ',
+                              ^^^^^^^^^^^^^^ Lint/DetectMetadataTrailingLeadingWhitespace: Metadata key or value has leading or trailing whitespace.
+        ))
+      end
+    RUBY
+  end
+end