Class: Datadog::AppSec::WAF::Handle

Inherits:
Object
  • Object
show all
Defined in:
lib/datadog/appsec/waf/handle.rb

Overview

Ruby representation of the ddwaf_handle in libddwaf See github.com/DataDog/libddwaf/blob/10e3a1dfc7bc9bb8ab11a09a9f8b6b339eaf3271/BINDING_IMPL_NOTES.md?plain=1#L4-L19

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(rule, limits: {}, obfuscator: {}) ⇒ Handle

Returns a new instance of Handle.



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# File 'lib/datadog/appsec/waf/handle.rb', line 11

def initialize(rule, limits: {}, obfuscator: {})
  rule_obj = Converter.ruby_to_object(rule)
  if rule_obj.null? || rule_obj[:type] == :ddwaf_object_invalid
    raise LibDDWAF::Error, "Could not convert object #{rule.inspect}"
  end

  config_obj = Datadog::AppSec::WAF::LibDDWAF::Config.new
  if config_obj.null?
    raise LibDDWAF::Error, 'Could not create config struct'
  end

  config_obj[:limits][:max_container_size]  = limits[:max_container_size]  || LibDDWAF::DEFAULT_MAX_CONTAINER_SIZE
  config_obj[:limits][:max_container_depth] = limits[:max_container_depth] || LibDDWAF::DEFAULT_MAX_CONTAINER_DEPTH
  config_obj[:limits][:max_string_length]   = limits[:max_string_length]   || LibDDWAF::DEFAULT_MAX_STRING_LENGTH
  config_obj[:obfuscator][:key_regex]       = FFI::MemoryPointer.from_string(obfuscator[:key_regex])   if obfuscator[:key_regex]
  config_obj[:obfuscator][:value_regex]     = FFI::MemoryPointer.from_string(obfuscator[:value_regex]) if obfuscator[:value_regex]
  config_obj[:free_fn] = LibDDWAF::ObjectNoFree

  @config = config_obj

  diagnostics_obj = LibDDWAF::Object.new

  @handle_obj = LibDDWAF.ddwaf_init(rule_obj, config_obj, diagnostics_obj)

  @diagnostics = Converter.object_to_ruby(diagnostics_obj)

  if @handle_obj.null?
    raise LibDDWAF::Error.new('Could not create handle', diagnostics: @diagnostics)
  end

  validate!
ensure
  LibDDWAF.ddwaf_object_free(diagnostics_obj) if diagnostics_obj
  LibDDWAF.ddwaf_object_free(rule_obj) if rule_obj
end

Instance Attribute Details

#config ⇒ Object (readonly)

Returns the value of attribute config.



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# File 'lib/datadog/appsec/waf/handle.rb', line 9

def config
  @config
end

#diagnostics ⇒ Object (readonly)

Returns the value of attribute diagnostics.



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# File 'lib/datadog/appsec/waf/handle.rb', line 9

def diagnostics
  @diagnostics
end

#handle_obj ⇒ Object (readonly)

Returns the value of attribute handle_obj.



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# File 'lib/datadog/appsec/waf/handle.rb', line 9

def handle_obj
  @handle_obj
end

Instance Method Details

#finalize ⇒ Object 



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# File 'lib/datadog/appsec/waf/handle.rb', line 47

def finalize
  invalidate!

  LibDDWAF.ddwaf_destroy(handle_obj)
end

#merge(data) ⇒ Object 



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# File 'lib/datadog/appsec/waf/handle.rb', line 64

def merge(data)
  data_obj = Converter.ruby_to_object(data, coerce: false)
  diagnostics_obj = LibDDWAF::Object.new
  new_handle = LibDDWAF.ddwaf_update(handle_obj, data_obj, diagnostics_obj)

  return if new_handle.null?

  diagnostics = Converter.object_to_ruby(diagnostics_obj)
  new_from_handle(new_handle, diagnostics, config)
ensure
  LibDDWAF.ddwaf_object_free(data_obj) if data_obj
  LibDDWAF.ddwaf_object_free(diagnostics_obj) if diagnostics_obj
end

#required_addresses ⇒ Object 



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# File 'lib/datadog/appsec/waf/handle.rb', line 53

def required_addresses
  valid!

  count = LibDDWAF::UInt32Ptr.new
  list = LibDDWAF.ddwaf_known_addresses(handle_obj, count)

  return [] if count == 0 # list is null

  list.get_array_of_string(0, count[:value])
end