Class: Sqreen::Legacy::Instrumentation

Inherits:
Object
  • Object
show all
Defined in:
lib/sqreen/legacy/instrumentation.rb

Constant Summary collapse

OVERTIME_METRIC = 
'request_overtime'.freeze
PRE_CB = 
'pre'.freeze
POST_CB = 
'post'.freeze
FAILING_CB = 
'failing'.freeze
@@override_semaphore = 
Mutex.new
@@overriden_singleton_methods = 
false
@@overriden_methods =

Overriden methods and callbacks globals

[]
@@registered_callbacks = 
CBTree.new
@@unovertimable_hookpoints = 
Set.new
@@record_request_hookpoints = 
Set.new
@@instrumented_pid = 
nil

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(metrics_engine = nil) ⇒ Instrumentation

Returns a new instance of Instrumentation.



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# File 'lib/sqreen/legacy/instrumentation.rb', line 774

def initialize(metrics_engine = nil)
  self.metrics_engine = metrics_engine
  return if metrics_engine.nil?
  ### init metric to count calls to sqreen
  metrics_engine.create_metric('name' => CallCountable::COUNT_CALLS,
                               'period' => 60,
                               'kind' => 'Sum')
  ### init metric to count request whitelist matches (ip or path whitelist)
  metrics_engine.create_metric('name' => Sqreen::Rules::RecordRequestContext::WHITELISTED_METRIC,
                               'period' => 60,
                               'kind' => 'Sum')
  ### init metric to count over budget hits
  metrics_engine.create_metric('name' => OVERTIME_METRIC,
                               'period' => 60,
                               'kind' => 'Sum')
end

Instance Attribute Details

#metrics_engine ⇒ Object

Returns the value of attribute metrics_engine.



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# File 'lib/sqreen/legacy/instrumentation.rb', line 721

def metrics_engine
  @metrics_engine
end

Class Method Details

.callback_wrapper_failing(callbacks, framework, budget, exception, _klass, method, instance, args, &block) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 188

def self.callback_wrapper_failing(callbacks, framework, budget, exception, _klass, method, instance, args, &block)
  all_start = Sqreen.time
  #Instrumentation.guard_call(method, []) do
    returns = []
    callbacks.each do |cb|
      next if cb.whitelisted?
      rule = cb.rule_name if cb.respond_to?(:rule_name)
      if budget && budget <= 0.0
        next if cb.overtimeable
      end
      Sqreen.log.debug { "running failing cb #{cb}" }
      begin
        start = Sqreen.time
        res = cb.failing(exception, instance, args, budget, &block)
        stop = Sqreen.time
        Sqreen.log.debug { "ran failing cb #{cb} => #{res.inspect}" }
        if budget
          budget -= (stop - start)
          cb.overtime! if budget <= 0.0
        end
        all_start += (stop - start)
        if !res.nil? && cb.respond_to?(:block) && (!cb.block && !Sqreen.config_get(:block_all_rules))
          Sqreen.log.debug do
            "#{cb} cannot block, overriding return value"
          end
          res = nil
        elsif res.is_a?(Hash)
          res[:rule_name] = rule
        end
        returns << res
      rescue StandardError => e
        Sqreen.log.warn { "we catch an exception: #{e.inspect}" }
        Sqreen.log.debug { e.backtrace }
        if cb.respond_to?(:record_exception)
          cb.record_exception(e)
        else
          Sqreen::RemoteException.record(e)
        end
        next
      end
      Sqreen::PerformanceNotifications.notify(rule || cb.class.name, FAILING_CB, start, stop)
    end
    all_stop = Sqreen.time
    if framework && budget && framework.remaining_perf_budget
      framework.remaining_perf_budget = budget - (all_stop - all_start)
    end
    Sqreen::PerformanceNotifications.notify('hooks_failing', FAILING_CB, all_start, all_stop)
    returns
 # end
rescue StandardError => e
  Sqreen.log.warn "we caught an exception between cbs: #{e.inspect}"
  Sqreen::RemoteException.record(e)
  []
end

.callback_wrapper_post(callbacks, framework, budget, _klass, method, return_val, instance, args, &block) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 133

def self.callback_wrapper_post(callbacks, framework, budget, _klass, method, return_val, instance, args, &block)
  all_start = Sqreen.time
  #Instrumentation.guard_call(method, []) do
    returns = []
    callbacks.reverse_each do |cb|
      next if cb.whitelisted?
      rule = cb.rule_name if cb.respond_to?(:rule_name)
      if budget && budget <= 0.0
        next if cb.overtimeable
      end
      Sqreen.log.debug { "running post cb #{cb}" }
      begin
        start = Sqreen.time
        res = cb.post(return_val, instance, args, budget, &block)
        stop = Sqreen.time
        Sqreen.log.debug { "ran post cb #{cb} => #{res.inspect}" }
        if budget
          budget -= (stop - start)
          cb.overtime! if budget <= 0.0
        end
        all_start += (stop - start)
        if !res.nil? && cb.respond_to?(:block) && (!cb.block && !Sqreen.config_get(:block_all_rules))
          Sqreen.log.debug do
            "#{cb} cannot block, overriding return value"
          end
          res = nil
        elsif res.is_a?(Hash)
          res[:rule_name] = rule
        end
        returns << res
      rescue StandardError => e
        Sqreen.log.warn { "we catch an exception: #{e.inspect}" }
        Sqreen.log.debug { e.backtrace }
        if cb.respond_to?(:record_exception)
          cb.record_exception(e)
        else
          Sqreen::RemoteException.record(e)
        end
        next
      end
      Sqreen::PerformanceNotifications.notify(rule || cb.class.name, POST_CB, start, stop)
    end
    all_stop = Sqreen.time
    if framework && budget && framework.remaining_perf_budget
      framework.remaining_perf_budget = budget - (all_stop - all_start)
    end
    Sqreen::PerformanceNotifications.notify('hooks_post', POST_CB, all_start, all_stop)
    returns
  #end
rescue StandardError => e
  Sqreen.log.warn { "we caught an exception between cbs: #{e.inspect}" }
  Sqreen::RemoteException.record(e)
  []
end

.callback_wrapper_pre(callbacks, framework, budget, _klass, method, instance, args, &block) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 76

def self.callback_wrapper_pre(callbacks, framework, budget, _klass, method, instance, args, &block)
  all_start = Sqreen.time
  #Instrumentation.guard_call(method, []) do
    returns = []
    callbacks.each do |cb|
      # If record_request is part of callbacks we should filter after it ran
      next if cb.whitelisted?
      rule = cb.rule_name if cb.respond_to?(:rule_name)
      if budget && budget <= 0.0
        next if cb.overtimeable
      end
      Sqreen.log.debug { "running pre cb #{cb}" }
      begin
        start = Sqreen.time
        res = cb.pre(instance, args, budget, &block)
        stop = Sqreen.time
        Sqreen.log.debug { "ran pre cb #{cb} => #{res.inspect}" }
        # The first few pre callbacks could not have a request & hence a budget just yet so we try harder to find it
        budget = framework.remaining_perf_budget if framework && !budget && Sqreen.performance_budget
        if budget
          budget -= (stop - start)
          cb.overtime! if budget <= 0.0
        end
        all_start += (stop - start)
        if !res.nil? && cb.respond_to?(:block) && (!cb.block && !Sqreen.config_get(:block_all_rules))
          Sqreen.log.debug do
            "#{cb} cannot block, overriding return value"
          end
          res = nil
        elsif res.is_a?(Hash)
          res[:rule_name] = rule
        end
        returns << res
        break if res.is_a?(Hash) && res[:skip_rem_cbs]
      rescue StandardError => e
        Sqreen.log.warn { "we catch an exception: #{e.inspect}" }
        Sqreen.log.debug { e.backtrace }
        if cb.respond_to?(:record_exception)
          cb.record_exception(e)
        else
          Sqreen::RemoteException.record(e)
        end
        next
      end
      Sqreen::PerformanceNotifications.notify(rule || cb.class.name, PRE_CB, start, stop)
    end
    all_stop = Sqreen.time
    framework.remaining_perf_budget = budget - (all_stop - all_start) if framework && budget
    Sqreen::PerformanceNotifications.notify('hooks_pre', PRE_CB, all_start, all_stop)
    returns
  #end
rescue StandardError => e
  Sqreen.log.warn { "we caught an exception between cbs: #{e.inspect}" }
  Sqreen::RemoteException.record(e)
  []
end

.callbacks ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 69

def self.callbacks
  @@registered_callbacks
end

.define_callback_method(meth, original_meth, klass_name) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 260

def self.define_callback_method(meth, original_meth, klass_name)
  @sqreen_multi_instr ||= nil

  proc do |*args, &block|
    Sqreen.log.debug { "Calling instrumented #{klass_name} #{original_meth} => #{meth}" }
    budget = nil
    skip_call = Thread.current[:sqreen_in_use]
    begin
      if !skip_call && Sqreen.performance_budget
        # Not using framework here to try to get a bit more perf by not loading cbs
        budget = Sqreen::SharedStorage.get(:performance_budget)
        skip_call = budget && budget <= 0.0 && !@@unovertimable_hookpoints.include?([klass_name, meth])
      end
    rescue StandardError => e
      Sqreen.log.warn "we catched an exception looking for overtime: #{e.inspect}"
      Sqreen::RemoteException.record(e)
    end
    if !skip_call && Process.pid != Instrumentation.instrumented_pid
      Sqreen.log.debug do
        "Instrumented #{Instrumentation.instrumented_pid} != PID #{Process.pid}"
      end
      skip_call = true
    end
    # If we are already overbudget let's not work at all
    return __send__(original_meth, *args, &block) if skip_call
    Instrumentation.guard_multi_call(self, meth, original_meth, args, block) do
      precbs, postcbs, failcbs = Instrumentation.callbacks.get(klass_name, meth)
      Thread.current[:sqreen_in_use] = true
      begin
        if budget && budget <= 0.0
          precbs = precbs.reject(&:overtimeable) if precbs
        end
        # We need the framework to set budget remaining time else don't look for it
        if budget
          cb_with_framework = nil
          cb_with_framework = precbs.find(&:framework) if precbs
          cb_with_framework = postcbs.find(&:framework) unless cb_with_framework || !postcbs
          cb_with_framework = failcbs.find(&:framework) unless cb_with_framework || !failcbs
          framework = cb_with_framework ? cb_with_framework.framework : nil
        else
          framework = nil
        end
      rescue StandardError => e
        Sqreen.log.warn "we catched an exception looking for framework: #{e.inspect}"
        Sqreen::RemoteException.record(e)
        framework = nil
      end

      skip = false
      result = nil

      if precbs && !precbs.empty?
        # pre callback
        returns = Instrumentation.callback_wrapper_pre(precbs, framework,
                                                       budget,
                                                       klass_name,
                                                       meth,
                                                       self,
                                                       args,
                                                       &block)
        returns.each do |ret|
          next unless ret.is_a? Hash
          case ret[:status]
          when :skip, 'skip'
            skip = true
            result = ret[:new_return_value] if ret.key? :new_return_value
            next
          when :modify_args, 'modify_args'
            args = ret[:args]
          when :raise, 'raise'
            Thread.current[:sqreen_in_use] = false
            raise ret[:exception] if ret.key?(:exception)
            raise Sqreen::AttackBlocked, "Sqreen blocked a security threat (type: #{ret[:rule_name]}). No action is required."
          end
        end
      end
      Thread.current[:sqreen_in_use] = false
      return result if skip
      begin
        result = __send__(original_meth, *args, &block)
      rescue StandardError => e
        Thread.current[:sqreen_in_use] = true
        budget = Sqreen.performance_budget && framework && framework.remaining_perf_budget
        failcbs = failcbs.reject(&:overtimeable) if failcbs && budget && budget <= 0.0
        raise e unless failcbs && !failcbs.empty?
        returns = Instrumentation.callback_wrapper_failing(failcbs,
                                                           framework,
                                                           budget,
                                                           e,
                                                           klass_name,
                                                           meth,
                                                           self,
                                                           args,
                                                           &block)
        will_retry = false
        will_raise = returns.empty?
        returns.each do |ret|
          will_raise = true if ret.nil?
          next unless ret.is_a? Hash
          case ret[:status]
          when :override, 'override'
            result = ret[:new_return_value] if ret.key? :new_return_value
          when :retry, 'retry'
            will_retry = true
          else # :reraise, 'reraise'
            will_raise = true
          end
        end
        raise e if will_raise
        retry if will_retry
        result
      else
        Thread.current[:sqreen_in_use] = true
        budget = Sqreen.performance_budget && framework && framework.remaining_perf_budget
        postcbs = postcbs.reject(&:overtimeable) if postcbs && budget && budget <= 0.0
        return result unless postcbs && !postcbs.empty?
        # post callback
        returns = Instrumentation.callback_wrapper_post(postcbs,
                                                        framework,
                                                        budget,
                                                        klass_name,
                                                        meth,
                                                        result,
                                                        self,
                                                        args,
                                                        &block)
        returns.each do |ret|
          next unless ret.is_a? Hash
          case ret[:status]
          when :raise, 'raise'
            raise ret[:exception] if ret.key?(:exception)
            raise Sqreen::AttackBlocked, "Sqreen blocked a security threat (type: #{ret[:rule_name]}). No action is required."
          when :override, 'override'
            result = ret[:new_return_value]
          else
            next
          end
        end
        result
      ensure
        Thread.current[:sqreen_in_use] = false
      end
    end
  end # end of proc
end

.guard_multi_call(instance, method, original_method, args, block) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 243

def self.guard_multi_call(instance, method, original_method, args, block)
  return yield unless @@overriden_singleton_methods
  key = [method]
  args.each { |e| key.push(e.object_id) }
  if key && @sqreen_multi_instr && @sqreen_multi_instr[instance.object_id].member?(key)
    return instance.__send__(original_method, *args, &block)
  end
  @sqreen_multi_instr ||= Hash.new { |h, k| h[k] = Set.new } # TODO: this should probably be a thread local
  @sqreen_multi_instr[instance.object_id].add(key)
  r = yield
  return r
ensure
  if @sqreen_multi_instr && @sqreen_multi_instr[instance.object_id] && @sqreen_multi_instr[instance.object_id].delete(key).empty?
    @sqreen_multi_instr.delete(instance.object_id)
  end
end

.instrumented_pid ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 65

def self.instrumented_pid
  @@instrumented_pid
end

.overriden ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 73

def self.overriden
  @@overriden_methods
end

.request_hookpoint_method(original_meth) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 406

def self.request_hookpoint_method(original_meth)
  proc do |*args, &block|
    has_notifications = Sqreen::PerformanceNotifications.listen_for?
    Sqreen::PerformanceNotifications::BinnedMetrics.start_request if has_notifications

    begin
      __send__(original_meth, *args, &block)
    ensure
      if has_notifications
        Sqreen::PerformanceNotifications.instrument('next_req_notifs', PRE_CB) do
          Sqreen::PerformanceNotifications::LogPerformance.next_request
          Sqreen::PerformanceNotifications::NewRelic.next_request
          Sqreen::PerformanceNotifications::BinnedMetrics.finish_request
        end
      end
    end
  end
end

.semaphore ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 61

def self.semaphore
  @@override_semaphore
end

Instance Method Details

#add_callback(cb) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 594

def add_callback(cb)
  @@override_semaphore.synchronize do
    klass = cb.klass
    method = cb.method
    key = [klass, method]

    if (call_count = ENV['SQREEN_DEBUG_CALL_COUNT'])
      call_count = JSON.parse(call_count)
      if cb.respond_to?(:rule_name) && call_count.key?(cb.rule_name)
        count = call_count[cb.rule_name]
        Sqreen.log.debug { "override rule:#{cb.rule_name} call_count:#{count.inspect}" }
        cb.instance_eval { @call_count_interval = call_count[cb.rule_name] }
      end
    end

    @@record_request_hookpoints << key if cb.is_a?(Sqreen::Rules::RecordRequestContext)

    already_overriden = @@overriden_methods.include? key

    if !already_overriden
      if is_class_method?(klass, method)
        Sqreen.log.debug { "overriding class method for #{cb}" }
        success = override_class_method(klass, method)
      elsif is_instance_method?(klass, method)
        Sqreen.log.debug { "overriding instance method for #{cb}" }
        success = override_instance_method(klass, method)
      else
        # FIXME: Override define_method and other dynamic ways to
        # The following should be monitored to make sure we
        # don't forget dynamically added methods:
        #  - define_method
        #  - method_added
        #  - method_missing
        #  ...
        #
        msg = "#{cb} is neither class or instance"
        raise Sqreen::NotImplementedYet, msg
      end

      @@overriden_methods += [key] if success
    else
      Sqreen.log.debug { "#{key} was already overriden" }
    end

    if klass != Object && klass != Kernel && !Sqreen.features['instrument_all_instances'] && !defined?(::JRUBY_VERSION)
      insts = 0
      ObjectSpace.each_object(klass) do |e|
        next if e.is_a?(Class) || e.is_a?(Module)
        next unless e.singleton_methods.include?(method.to_sym)
        insts += 1 if override_singleton_method(e, klass, method)
      end
      if insts > 0
        Sqreen.log.debug { "Reinstrumented #{insts} instances of #{klass}" }
      end
    end

    Sqreen.log.debug { "Adding callback #{cb} for #{klass} #{method}" }
    @@registered_callbacks.add(cb)
    @@unovertimable_hookpoints << key unless cb.overtimeable
    @@instrumented_pid = Process.pid
  end
end

#adjust_method_name(method) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 540

def adjust_method_name(method)
  method.to_s
end

#get_saved_method_name(meth, suffix = nil) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 473

def get_saved_method_name(meth, suffix = nil)
  "#{meth}_sq#{suffix}_not_modified".to_sym
end

#hardcoded_callbacks(framework) ⇒ Array<Sqreen::CB>

Returns:



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# File 'lib/sqreen/legacy/instrumentation.rb', line 724

def hardcoded_callbacks(framework)
  [
    ### callback for performing sec responses based on ip
    ### init redefined to implement smartass way to hook it upon the
    ### framework's middleware #call
    Sqreen::Rules::RunReqStartActions.new(framework),
    ### callback for performing sec responses based on user
    Sqreen::Rules::RunUserActions.new(Sqreen, :identify, 0),
    ### callback for performing sec responses based on user
    Sqreen::Rules::RunUserActions.new(Sqreen, :auth_track, 1),
  ]
end

#instrument!(rules, framework) ⇒ Object

Instrument the application code using the rules

Parameters:



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# File 'lib/sqreen/legacy/instrumentation.rb', line 740

def instrument!(rules, framework)
  ### set up rule signature verifier
  verifier = nil
  if Sqreen.features['rules_signature'] &&
     Sqreen.config_get(:rules_verify_signature) == true &&
     !defined?(::JRUBY_VERSION)
    verifier = Sqreen::SqreenSignedVerifier.new
  else
    Sqreen.log.debug('Rules signature is not enabled')
  end

  ### force clean instrumentation callback list
  remove_all_callbacks # Force cb tree to be empty before instrumenting

  ### for each rule description, transform into format for adding callback
  rules.each do |rule|
    rcb = Sqreen::Rules.cb_from_rule(rule, self, metrics_engine, verifier)
    next unless rcb
    ### attach framework to callback
    rcb.framework = framework
    ### add callback
    add_callback(rcb)
  end

  # add hardcoded callbacks, observing priority
  hardcoded_callbacks(framework).each { |cb| add_callback(cb) }

  ### globally declare instrumentation ready
  ### from within instance method? not even thread local?
  Sqreen.instrumentation_ready = true

  Sqreen.log.info('Instrumentation activated')
end

#is_class_method?(klass, method) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/sqreen/legacy/instrumentation.rb', line 555

def is_class_method?(klass, method)
  method = adjust_method_name(method)
  klass.singleton_methods.include? method
end

#is_instance_method?(klass, method) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/sqreen/legacy/instrumentation.rb', line 549

def is_instance_method?(klass, method)
  method = adjust_method_name(method)
  klass.instance_methods.include?(method) ||
    klass.private_instance_methods.include?(method)
end

#override_class_method(klass, meth) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 425

def override_class_method(klass, meth)
  original = meth.to_sym
  saved_meth_name = get_saved_method_name(meth).to_sym
  new_method      = "#{meth}_modified".to_sym

  klass.singleton_class.instance_eval do
    alias_method saved_meth_name, original

    p = Instrumentation.define_callback_method(original, saved_meth_name, klass)
    define_method(new_method, p)

    private new_method

    method_kind = nil
    if public_method_defined?(original)
      method_kind = :public
    elsif protected_method_defined?(original)
      method_kind = :protected
    elsif private_method_defined?(original)
      method_kind = :private
    end

    alias_method original, new_method
    __send__(method_kind, original)
    private saved_meth_name
  end
end

#override_instance_method(klass_name, meth) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 477

def override_instance_method(klass_name, meth)
  saved_meth_name = get_saved_method_name(meth)
  new_method      = "#{meth}_modified".to_sym

  # do not include ancestors o/wise we might get a saved method from a
  # superclass which is never called because the original name
  # (instrumented) method of the superclass has been overridden
  private_meths = klass_name.private_instance_methods(false)
  if private_meths.include?(saved_meth_name)
    Sqreen.log.debug { "#{saved_meth_name} found #{klass_name}##{meth} already instrumented" }
    return saved_meth_name
  end

  p = Instrumentation.define_callback_method(meth, saved_meth_name,
                                             klass_name)
  method_kind = nil
  klass_name.class_eval do
    alias_method saved_meth_name, meth

    define_method(new_method, p)

    if @@record_request_hookpoints.include?([klass_name, meth])
      p = Instrumentation.request_hookpoint_method(new_method)
      new_method = "#{new_method}_req_hp_wrapper"
      define_method(new_method, p)
    end

    if public_method_defined?(meth)
      method_kind = :public
    elsif protected_method_defined?(meth)
      method_kind = :protected
    elsif private_method_defined?(meth)
      method_kind = :private
    end
    alias_method meth, new_method
    private saved_meth_name
    private new_method
    __send__(method_kind, meth)
  end
  saved_meth_name
end

#override_singleton_method(instance, klass_name, meth) ⇒ Object

is that actually used? if so, do not attempt to alter frozen instances Override a singleton method on an instance

Raises:



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# File 'lib/sqreen/legacy/instrumentation.rb', line 570

def override_singleton_method(instance, klass_name, meth)
  @@overriden_singleton_methods = true
  saved_meth_name = get_saved_method_name(meth, 'singleton')
  if instance.respond_to?(saved_meth_name, true)
    Sqreen.log.debug { "#{saved_meth_name} found #{instance.class}##{instance.object_id} already instrumented" }
    return nil
  elsif instance.frozen?
    Sqreen.log.debug { "#{instance.class}##{instance.object_id} is frozen, not reinstrumenting" }
    return nil
  end
  raise Sqreen::NotImplementedYet, "#{instance.inspect} doesn't respond to define_singleton_method" unless instance.respond_to?(:define_singleton_method)
  p = Instrumentation.define_callback_method(meth, saved_meth_name,
                                             klass_name)
  instance.define_singleton_method(saved_meth_name, instance.method(meth))
  instance.define_singleton_method(meth, p)
  # Hide saved method (its only available in this syntax)
  eval <<-RUBY, binding, __FILE__, __LINE__ + 1
  class << instance
    private :#{saved_meth_name}
  end
  saved_meth_name
  RUBY
end

#remove_all_callbacks ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 711

def remove_all_callbacks
  @@override_semaphore.synchronize do
    @@registered_callbacks.entries.each do |cb|
      remove_callback_no_lock(cb)
    end
    Sqreen.instrumentation_ready = false
    Sqreen.log.info('Instrumentation deactivated')
  end
end

#remove_callback(cb) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 657

def remove_callback(cb)
  @@override_semaphore.synchronize do
    remove_callback_no_lock(cb)
  end
end

#remove_callback_no_lock(cb) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 663

def remove_callback_no_lock(cb)
  klass = cb.klass
  method = cb.method

  key = [klass, method]

  already_overriden = @@overriden_methods.include? key
  unless already_overriden
    Sqreen.log.debug { "#{key} apparently not overridden" }
  end

  defined_cbs = @@registered_callbacks.get(klass, method).flatten

  nb_removed = 0
  defined_cbs.each do |found_cb|
    if found_cb == cb
      Sqreen.log.debug { "Removing callback #{found_cb}" }
      @@registered_callbacks.remove(found_cb)
      nb_removed += 1
    else
      Sqreen.log.debug { "Not removing callback #{found_cb} (remains #{defined_cbs.size} cbs)" }
    end
  end

  return unless nb_removed == defined_cbs.size

  Sqreen.log.debug { "Removing overriden method #{key}" }
  @@overriden_methods.delete(key)

  if is_class_method?(klass, method)
    unoverride_class_method(klass, method)
  elsif is_instance_method?(klass, method)
    unoverride_instance_method(klass, method)
  else
    ### Module#prepend will take care of that
    # FIXME: Override define_method and other dynamic ways to
    # The following should be monitored to make sure we
    # don't forget dynamically added methods:
    #  - define_method
    #  - method_added
    #  - method_missing
    #  ...
    #
    msg = "#{cb} is neither singleton or instance"
    raise Sqreen::NotImplementedYet, msg
  end
end

#unoverride_class_method(klass, meth) ⇒ Object

bad idea anyway WARNING We do not actually remove ‘meth`



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# File 'lib/sqreen/legacy/instrumentation.rb', line 521

def unoverride_class_method(klass, meth)
  saved_meth_name = get_saved_method_name(meth)
  method_kind = nil

  klass.singleton_class.instance_eval do
    if public_method_defined?(meth.to_sym)
      method_kind = :public
    elsif protected_method_defined?(original)
      method_kind = :protected
    elsif private_method_defined?(meth.to_sym)
      method_kind = :private
    end
    alias_method meth.to_sym, saved_meth_name.to_sym
    __send__(method_kind, meth.to_sym)
  end
end

#unoverride_instance_method(obj, meth) ⇒ Object 



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# File 'lib/sqreen/legacy/instrumentation.rb', line 453

def unoverride_instance_method(obj, meth)
  saved_meth_name = get_saved_method_name(meth)

  method_kind = nil
  obj.class_eval do
    # Note: As a lambda the following will crash ruby 2.2.3p173
    if public_method_defined?(meth)
      method_kind = :public
    elsif protected_method_defined?(meth)
      method_kind = :protected
    elsif private_method_defined?(meth)
      method_kind = :private
    end
    alias_method meth, saved_meth_name
    __send__(method_kind, meth)

    remove_method saved_meth_name
  end
end

#valid_method?(obj, method) ⇒ Boolean

Does this object or an instance of it respond_to method?

Returns:

  • (Boolean) 


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# File 'lib/sqreen/legacy/instrumentation.rb', line 561

def valid_method?(obj, method)
  return true if is_class_method?(obj, method)
  return false unless obj.respond_to?(:instance_methods)
  is_instance_method?(obj, method)
end