monero/contrib/epee/include/net/levin_protocol_handler.h
moneromooo-monero 7dbf76d0da
Fix an object lifetime bug in net load tests
The commands handler must not be destroyed before the config
object, or we'll be accessing freed memory.

An earlier attempt at using boost::shared_ptr to control object
lifetime turned out to be very invasive, though would be a
better solution in theory.
2017-10-09 16:46:42 +01:00

184 lines
5.9 KiB
C++

// Copyright (c) 2006-2013, Andrey N. Sabelnikov, www.sabelnikov.net
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// * Neither the name of the Andrey N. Sabelnikov nor the
// names of its contributors may be used to endorse or promote products
// derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
#ifndef _LEVIN_PROTOCOL_HANDLER_H_
#define _LEVIN_PROTOCOL_HANDLER_H_
#include <boost/uuid/uuid_generators.hpp>
#include "levin_base.h"
#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "net"
namespace epee
{
namespace levin
{
template<class t_connection_context = net_utils::connection_context_base>
struct protocl_handler_config
{
levin_commands_handler<t_connection_context>* m_pcommands_handler;
void (*m_pcommands_handler_destroy)(levin_commands_handler<t_connection_context>*);
~protocl_handler_config() { if (m_pcommands_handler && m_pcommands_handler_destroy) (*m_pcommands_handler_destroy)(m_pcommands_handler); }
};
template<class t_connection_context = net_utils::connection_context_base>
class protocol_handler
{
public:
typedef t_connection_context connection_context;
typedef protocl_handler_config<t_connection_context> config_type;
protocol_handler(net_utils::i_service_endpoint* psnd_hndlr, config_type& config, t_connection_context& conn_context);
virtual ~protocol_handler(){}
virtual bool handle_recv(const void* ptr, size_t cb);
bool after_init_connection(){return true;}
private:
enum connection_data_state
{
conn_state_reading_head,
conn_state_reading_body
};
config_type& m_config;
t_connection_context& m_conn_context;
net_utils::i_service_endpoint* m_psnd_hndlr;
std::string m_cach_in_buffer;
connection_data_state m_state;
bucket_head m_current_head;
};
template<class t_connection_context>
protocol_handler<t_connection_context>::protocol_handler(net_utils::i_service_endpoint* psnd_hndlr, config_type& config, t_connection_context& conn_context):
m_config(config),
m_conn_context(conn_context),
m_psnd_hndlr(psnd_hndlr),
m_state(conn_state_reading_head),
m_current_head(bucket_head())
{}
template<class t_connection_context>
bool protocol_handler<t_connection_context>::handle_recv(const void* ptr, size_t cb)
{
if(!m_config.m_pcommands_handler)
{
LOG_ERROR_CC(m_conn_context, "Command handler not set!");
return false;
}
m_cach_in_buffer.append((const char*)ptr, cb);
bool is_continue = true;
while(is_continue)
{
switch(m_state)
{
case conn_state_reading_head:
if(m_cach_in_buffer.size() < sizeof(bucket_head))
{
if(m_cach_in_buffer.size() >= sizeof(uint64_t) && *((uint64_t*)m_cach_in_buffer.data()) != LEVIN_SIGNATURE)
{
LOG_ERROR_CC(m_conn_context, "Signature mismatch on accepted connection");
return false;
}
is_continue = false;
break;
}
{
bucket_head* phead = (bucket_head*)m_cach_in_buffer.data();
if(LEVIN_SIGNATURE != phead->m_signature)
{
LOG_ERROR_CC(m_conn_context, "Signature mismatch on accepted connection");
return false;
}
m_current_head = *phead;
}
m_cach_in_buffer.erase(0, sizeof(bucket_head));
m_state = conn_state_reading_body;
break;
case conn_state_reading_body:
if(m_cach_in_buffer.size() < m_current_head.m_cb)
{
is_continue = false;
break;
}
{
std::string buff_to_invoke;
if(m_cach_in_buffer.size() == m_current_head.m_cb)
buff_to_invoke.swap(m_cach_in_buffer);
else
{
buff_to_invoke.assign(m_cach_in_buffer, 0, (std::string::size_type)m_current_head.m_cb);
m_cach_in_buffer.erase(0, (std::string::size_type)m_current_head.m_cb);
}
if(m_current_head.m_have_to_return_data)
{
std::string return_buff;
m_current_head.m_return_code = m_config.m_pcommands_handler->invoke(m_current_head.m_command, buff_to_invoke, return_buff, m_conn_context);
m_current_head.m_cb = return_buff.size();
m_current_head.m_have_to_return_data = false;
std::string send_buff((const char*)&m_current_head, sizeof(m_current_head));
send_buff += return_buff;
if(!m_psnd_hndlr->do_send(send_buff.data(), send_buff.size()))
return false;
}
else
m_config.m_pcommands_handler->notify(m_current_head.m_command, buff_to_invoke, m_conn_context);
}
m_state = conn_state_reading_head;
break;
default:
LOG_ERROR_CC(m_conn_context, "Undefined state in levin_server_impl::connection_handler, m_state=" << m_state);
return false;
}
}
return true;
}
}
}
#endif //_LEVIN_PROTOCOL_HANDLER_H_