User/custom soap headers crash application when ServiceClient::Invoke fails

[Mike]

User/custom soap headers crash application when ServiceClient::Invoke fails (when server does not respond).

void staff::ServiceClient::AddHeader(DataObject& rdoHeader) 

adds headers this way:

void ServiceClient::AddHeader(DataObject& rdoHeader)

{

    STAFF_ASSERT(m_pSvcClient, "Service client is not initialized");

    axis2_svc_client_add_header(m_pSvcClient, m_pEnv, rdoHeader);

}  

Observations:

AddHeader takes axiom node without doing any copy (does not clone) what implies that  rdoHeader MUST exist when DataObject ServiceClient::Invoke(DataObject& rdoPayload)  is called. 

Implifications:

In DataObject ServiceClient::Invoke(DataObject& rdoPayload)

Custom headers are cleared to avoid double free.

    if (m_pOptions) // unset http headers to avoid double free

       axis2_options_set_http_headers(*m_pOptions, m_pEnv, NULL);

It can be accepted as long as there is no http transmission error type (endpoint does not respond).

When it happens we have:

- pAxiomResponseNode is null

- axis2c implementation frees also axiom nodes of headers passed via ServiceClient::AddHeader (It is done during axis2_svc_client_send_receive call)

so in this case, rdoHeader object points to axiom node (memory block) that has been freed by axis2c code and application crashes.

I think that I should be done this way:

// Safe copy

  void ServiceClient::AddHeader(DataObject& rdoHeader)

  {

    STAFF_ASSERT(m_pSvcClient, "Service client is not initialized");

    staff::DataObject clone = rdoHeader.Clone();

    axis2_svc_client_add_header(m_pSvcClient, m_pEnv, clone);

  } 

and in this case 

DataObject ServiceClient::Invoke(DataObject& rdoPayload)

should be without

    if (m_pOptions) // unset http headers to avoid double free

       axis2_options_set_http_headers(*m_pOptions, m_pEnv, NULL);

Note that this way passed headers via ServiceClient::AddHeader

will be freed on service end or on next client call/request (according to axis2c code).

 

[Dmitry Utkin]

Hi Mike,

Could you please provide the example to reproduce the issue?

Please attach it to your message.

четверг, 4 сентября 2014 г., 15:04:12 UTC+4 пользователь Mike написал:

[Mike]

Test code:

std::string address("http://10.0.0.222/notexisting");

std::string sessionId;

std::string instanceId;

service.Init(address, sessionId, instanceId); 

service.test();

// ---------------------------------------------------------------------------------------

#include <staff/common/IService.h>

class MyService : public staff::IService

{

public:

    virtual bool test() = 0;

};

// -----------------------------------------------------------------------

// This file generated by staff_codegen

// For more information please visit: http://code.google.com/p/staff/

// DO NOT EDIT

#ifndef _myserviceProxy_h_

#define _myserviceProxy_h_

#include <staff/client/ServiceClient.h>

#include "myservice.h"

//! Proxy for component service MyService

class MyServiceProxy: public MyService

{

public:

  MyServiceProxy();

  virtual ~MyServiceProxy();

  void Init(const std::string& sServiceUri, const std::string& sSessionId, const std::string& sInstanceId);

  void Deinit();

  virtual staff::ServiceClient* GetClient();

  bool test();

private:

  mutable staff::ServiceClient m_tClient;

  std::string m_sServiceUri;

};

namespace staff

{

  class DataObject;

}

#endif

// ---------------------------------------------------------------------------

// This file generated by staff_codegen

// For more information please visit: http://code.google.com/p/staff/

// DO NOT EDIT

#include "stdafx.h"

#include <memory>

#include <staff/utils/SharedPtr.h>

#include <staff/utils/Log.h>

#include <staff/utils/fromstring.h>

#include <staff/utils/tostring.h>

#include <staff/utils/HexBinary.h>

#include <staff/utils/Base64Binary.h>

#include <staff/common/DataObject.h>

#include <staff/common/Attribute.h>

#include <staff/common/Exception.h>

#include <staff/common/Operation.h>

#include <staff/client/ServiceFactory.h>

#include <staff/client/IProxyAllocator.h>

#include <staff/client/ICallback.h>

#include <staff/client/Options.h>

#include "myserviceProxy.h"

namespace staff

{

///////////////////////////////////////////////////////////////////////////////////////////////////////

// typedef deserializators

}

///////////////////////////////////////////////////////////////////////////////////////////////////////

// classes implementation

// proxy allocator

class MyServiceProxyAllocator: public staff::IProxyAllocator

{

public:

  MyServiceProxyAllocator()

  {

    try

    {

      staff::ServiceFactory::Inst().RegisterProxyAllocator(typeid(MyService).name(), *this);

    }

    STAFF_CATCH_ALL_DESCR("Failed to register proxy allocator MyService");

  }

  virtual staff::IService* AllocateProxy(const std::string& sServiceUri,

                                         const std::string& sSessionId,

                                         const std::string& sInstanceId)

  {

    std::auto_ptr<MyServiceProxy> tpProxy(new MyServiceProxy);

    tpProxy->Init(sServiceUri, sSessionId, sInstanceId);

    return tpProxy.release();

  }

  virtual staff::IService* AllocateProxy(const std::string& sBaseUri,

                                         const std::string& sServiceName,

                                         const std::string& sSessionId,

                                         const std::string& sInstanceId)

  {

    std::auto_ptr<MyServiceProxy> tpProxy(new MyServiceProxy);

    tpProxy->Init(sBaseUri + (sServiceName.empty() ? "MyService" : sServiceName),

                  sSessionId, sInstanceId);

    return tpProxy.release();

  }

};

MyServiceProxyAllocator tMyServiceProxyAllocatorInitializer;

// asynch proxies

// service proxy

MyServiceProxy::MyServiceProxy()

{

}

MyServiceProxy::~MyServiceProxy()

{

  try

  {

    Deinit();

  }

  STAFF_CATCH_ALL;

}

void MyServiceProxy::Init(const std::string& sServiceUri, const std::string& sSessionId, const std::string& sInstanceId)

{

  staff::IService::Init("MyService", sSessionId, sInstanceId);

  m_sServiceUri = !sServiceUri.empty() ? sServiceUri : "http://localhost:9090/axis2/services/MyService";

  m_tClient.Init(m_sServiceUri);

  staff::Options& rOptions = m_tClient.GetOptions();

  rOptions.SetSessionId(sSessionId);

  if (!sInstanceId.empty())

  {

    staff::Operation tOperation("CreateInstance");

    tOperation.Request().CreateChild("sInstanceId").SetText(sInstanceId);

    tOperation.SetResponse(m_tClient.Invoke(tOperation.Request()));

    if (m_tClient.GetLastResponseHasFault())

    {

      STAFF_ASSERT_SOAPFAULT(!tOperation.IsFault(), tOperation.GetFaultCode(),

                             tOperation.GetFaultString(), tOperation.GetFaultDetail()); // soap fault

      STAFF_THROW(::staff::RemoteException, "Failed to invoke service: " +

                  tOperation.GetResponse().ToString()); // other fault

    }

    rOptions.SetInstanceId(sInstanceId);

  }

}

void MyServiceProxy::Deinit()

{

  if (!staff::IService::GetInstanceId().empty())

  {

    staff::Operation tOperation("FreeInstance");

    tOperation.Request().CreateChild("sInstanceId").SetText(staff::IService::GetInstanceId());

    tOperation.SetResponse(m_tClient.Invoke(tOperation.Request()));

    if (m_tClient.GetLastResponseHasFault())

    {

      STAFF_ASSERT_SOAPFAULT(!tOperation.IsFault(), tOperation.GetFaultCode(),

                             tOperation.GetFaultString(), tOperation.GetFaultDetail()); // soap fault

      STAFF_THROW(::staff::RemoteException, "Failed to invoke service: " +

                  tOperation.GetResponse().ToString()); // other fault

    }

  }

}

staff::ServiceClient* MyServiceProxy::GetClient()

{

  return &m_tClient;

}

bool MyServiceProxy::test()

{

  staff::Operation tOperation("test");

  staff::DataObject& rdoRequest = tOperation.Request();

  rdoRequest.SetNamespaceUriGenPrefix("http://tempui.org/MyService");

  // synchronous call

  

  staff::DataObject myHeader("MyHeader");

  myHeader.SetText("My data.");

  m_tClient.AddHeader(myHeader);

  tOperation.SetResponse(m_tClient.Invoke(rdoRequest));

  if (m_tClient.GetLastResponseHasFault())

  {

    STAFF_ASSERT_SOAPFAULT(!tOperation.IsFault(), tOperation.GetFaultCode(),

                           tOperation.GetFaultString(), tOperation.GetFaultDetail()); // soap fault

    STAFF_THROW(::staff::RemoteException, "Failed to invoke service: " + tOperation.GetResponse().ToString()); // other fault

  }

  const staff::DataObject& rdoResult = tOperation.ResultOpt();

  bool tReturn = 0;

  STAFF_ASSERT(rdoResult.GetValue(tReturn), "Invalid value for element tReturn");

  return tReturn;

}

// ----------------------------------------------------------------------------------

[Dmitry Utkin]

Hi Mike,

I tried to to reproduce the issue you described, but was unable to do that (under Linux).

I used interface and modified version of proxy you provided.

Valgrind does not show any memory errors too.

Which version of Axis2/C you are using? Which is the version of Visual Studio?

четверг, 4 сентября 2014 г., 16:13:33 UTC+4 пользователь Mike написал:

[Mike]

Hi,

Sorry for late response.

I have both staff and axis compiled under windows 7 with visual studio 2010

where 

staff is

    LIBRARY_VERSION=1.99.2

    PACKAGE_VERSION=2.0.0-b1

unofficial axis

   in changelog it says that it is Axis2/C (1.6.0)

Mike