Class: Ratonvirus::Scanner::Base

Inherits:
Object
  • Object
show all
Includes:
Support::Callbacks
Defined in:
lib/ratonvirus/scanner/base.rb

Direct Known Subclasses

Eicar

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(configuration = {}) ⇒ Base

Returns a new instance of Base.



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# File 'lib/ratonvirus/scanner/base.rb', line 17

def initialize(configuration = {})
  @config = default_config.merge!(configuration)

  # Make the following callbacks available:
  # - before_process_scan
  # - before_scan
  # - after_scan
  # - after_process_scan
  #
  # Usage:
  #   module CustomAddon
  #     def self.extended(validator)
  #       validator.before_process_scan :around_scan
  #       validator.before_scan :do_something
  #       validator.after_scan :do_something
  #       validator.before_process_scan :around_scan
  #     end
  #
  #     private
  #       def around_scan(resource)
  #         puts resource.inspect
  #         # Depends on the provided resource, e.g.
  #         # => #<ActiveStorage::Attached::One: ...>
  #         # => #<ActiveStorage::Attached::Many: ...>
  #         # => #<CarrierWave::Uploader::Base: ...>
  #         # => #<File: ...>
  #         # => #<String: ...>
  #       end
  #
  #       def do_something(processable)
  #         puts processable.inspect
  #         # => #<Ratonvirus::Processable: ...>
  #       end
  #   end
  define_callbacks :process_scan # Around the scan for the whole resource
  define_callbacks :scan # The actual scan for individual assets

  setup
end

Instance Attribute Details

#config ⇒ Object (readonly)

:errors - Only available after ‘virus?` has been called.



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# File 'lib/ratonvirus/scanner/base.rb', line 15

def config
  @config
end

#errors ⇒ Object (readonly)

:errors - Only available after ‘virus?` has been called.



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# File 'lib/ratonvirus/scanner/base.rb', line 15

def errors
  @errors
end

Class Method Details

.executable? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ratonvirus/scanner/base.rb', line 9

def executable?
  false
end

Instance Method Details

#available? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ratonvirus/scanner/base.rb', line 67

def available?
  return @available unless @available.nil?

  @available = self.class.executable?
end

#setup ⇒ Object

This method can be overridden in the scanner implementations in case the setup needs to be customized.



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# File 'lib/ratonvirus/scanner/base.rb', line 59

def setup
  if config[:force_availability]
    @available = true
  else
    available?
  end
end

#virus?(resource) ⇒ Boolean

The virus? method runs the scan and returns a boolean indicating whether the scanner rejected the given resource or detected a virus. Scanning is mainly used to detect viruses but the scanner can reject the resource also because of other reasons than it detecting a virus.

All these cases, however, should be interpreted as the resource containing a virus because in case there is e.g. a client error, we cannot be sure whether the file contains a virus and therefore it’s safer to assume the worst.

Possible errors are:

  • :antivirus_virus_detected - A virus was detected.

  • :antivirus_file_not_found - The scanner did not find the file for the given resource.

  • :antivirus_client_error - There was a client error at the scanner, e.g. it is temporarily unavailable.

Returns:

  • (Boolean) 


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# File 'lib/ratonvirus/scanner/base.rb', line 89

def virus?(resource)
  prepare

  @errors = []

  run_callbacks :process_scan, resource do
    storage.process(resource) do |processable|
      # In case multiple processables are processed, make sure that the
      # local errors for each scan refer only to that scan.
      errors_before = @errors
      @errors = []

      begin
        scan(processable)
      ensure
        # Make sure that after the scan, the errors are reverted back to
        # all errors.
        @errors = errors_before + @errors
      end
    end
  end

  # Only show unique errors
  errors.uniq!

  errors.any?
end