merged PingRotate into PingScheduler; fixed save/load of cache to/from file; started...
[pingcheck] / src / icmp / icmppinger.cpp
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1// Boost pinger (c) 2011 by Guilherme Maciel Ferreira / Intra2net AG
2// Based upon work copyright (c) 2003-2010 Christopher M. Kohlhoff (ping.cpp)
3//
4// Distributed under the Boost Software License, Version 1.0.
5// (See accompanying file LICENSE_1_0.txt or copy at
6// http://www.boost.org/LICENSE_1_0.txt)
511ced78 7#include "icmp/icmppinger.h"
9c55ecd3 8
47848853 9#include <errno.h>
47848853 10
4ea9706c
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11#include <ostream>
12
9c55ecd3 13#include <boost/bind.hpp>
451c9121
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14#include <boost/date_time/posix_time/posix_time.hpp>
15#include <boost/date_time/posix_time/posix_time_types.hpp>
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16#include <boost/uuid/uuid.hpp>
17#include <boost/uuid/uuid_generators.hpp>
41d175b0 18#include <boost/foreach.hpp>
55978089 19
301610ca
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20#include <logfunc.hpp>
21
780b0bca 22#include "boost_assert_handler.h"
af68f845 23#include "icmp/icmppacketfactory.h"
41d175b0 24#include "host/networkinterface.hpp"
4ea9706c 25
a7c2eb51 26using namespace std;
2bf8720f
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27using boost::asio::const_buffers_1;
28using boost::asio::io_service;
29using boost::asio::ip::address;
30using boost::asio::ip::icmp;
cd395966 31using boost::function;
2bf8720f 32using boost::posix_time::microsec_clock;
2bf8720f 33using boost::posix_time::seconds;
e58d7507 34using boost::shared_ptr;
301610ca 35using I2n::Logger::GlobalLogger;
2d591235 36
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37using boost::asio::ip::icmp;
38
4ea9706c 39//-----------------------------------------------------------------------------
87e525ff 40// IcmpPinger
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41//-----------------------------------------------------------------------------
42
1ece191b
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43/**
44 * @brief factory function for IcmpPingers, ensures that set_myself is set
45 *
46 * @returns a shared pointer to a Pinger
47 */
48PingerItem IcmpPinger::create(
49 const IoServiceItem io_serv,
50 const icmp::socket::protocol_type &protocol,
51 const string &source_network_interface,
52 const int echo_reply_timeout_in_sec )
53{
54 // get distributor
55 IcmpPacketDistributorItem distributor = IcmpPacketDistributor::get_distributor(
56 icmp::v4(), source_network_interface, io_serv);
57
58 // create pinger
f076f8d4 59 IcmpPinger *ptr = new IcmpPinger(io_serv, protocol, echo_reply_timeout_in_sec, distributor);
1ece191b 60 IcmpPingerItem shared_ptr_(ptr);
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61
62 // keep weak pointer to self
63 //shared_ptr_->set_myself( weak_ptr ); //Error: Pinger::set_myself is protected
d3bb7afe 64 ptr->set_myself( shared_ptr_ );
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65
66 // register in distributor
67 distributor->register_pinger(shared_ptr_);
68
69 // done, return shared ptr
70 return shared_ptr_;
71}
9ae5d9cb 72
0697580f
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73/**
74 * @brief Parameterized constructor.
5b008ada 75 *
ab2cb1ef 76 * @param io_serv The one @c io_service object that controls async processing
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77 * @param protocol The network layer protocol to use.
78 * @param source_network_interface The network interface name from where to
79 * send the packets.
80 * @param echo_reply_timeout_in_sec The amount of time to wait for a reply.
0697580f 81 */
87e525ff 82IcmpPinger::IcmpPinger(
365036be 83 const IoServiceItem io_serv,
fc3754b0 84 const icmp::socket::protocol_type &protocol,
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85 const int echo_reply_timeout_in_sec,
86 const IcmpPacketDistributorItem distributor
ced28dc7 87) :
e0a99ac4 88 PacketDistributor( distributor ),
33f408b1 89 DestinationEndpoint(),
5b008ada 90 Protocol( protocol ),
365036be 91 IcmpPacketReceiveTimer( *io_serv ),
87e525ff 92 Identifier( 0 ),
33f408b1 93 SequenceNumber( 0 ),
a7c2eb51 94 TimeSent( microsec_clock::universal_time() ),
0697580f 95 ReplyReceived( false ),
e08ab6c9 96 EchoReplyTimeoutInSec( echo_reply_timeout_in_sec ),
24e706c4 97 PingerStatus( PingStatus_NotSent ),
e0a99ac4 98 PingDoneCallback()
4ea9706c 99{
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100 // Create "unique" identifier
101 boost::uuids::random_generator random_gen;
102 boost::uuids::uuid random_tag = random_gen();
103
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104 BOOST_ASSERT( sizeof(Identifier) <= random_tag.size() );
105 memcpy( &Identifier, random_tag.data, sizeof(Identifier) );
ced28dc7
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106}
107
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108/**
109 * @brief Destructor.
110 */
87e525ff 111IcmpPinger::~IcmpPinger()
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112{
113}
114
e08ab6c9 115/**
d8b4a7e7 116 * @brief Ping a destination address from an available local source.
e08ab6c9 117 *
2035d00e 118 * @param destination_ip The address of the host to ping.
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119 * @param destination_port The port at the destination host to ping.
120 * @param done_handler Done handler will be called on successful ping or timeout.
121 *
122 * @return void.
b1a82632 123 */
87e525ff 124void IcmpPinger::ping(
23f51766 125 const address &destination_ip,
080ca508 126 const uint16_t /*destination_port*/, // the ICMP protocol does not use ports
20976656 127 function<void(bool)> ping_done_callback
87e525ff 128)
ced28dc7 129{
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130 PingDoneCallback = ping_done_callback;
131
e1e27b3c 132 // Prepare ping
c0950a05 133 set_ping_status( PingStatus_NotSent );
e1e27b3c 134
39e10382 135 set_destination_endpoint( destination_ip );
4ea9706c 136
1ece191b 137 start_send();
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138}
139
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140void IcmpPinger::stop_pinging()
141{
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142 GlobalLogger.debug()
143 << DestinationEndpoint.address().to_string()
144 << ": stop_pinging" << endl;
145
146 GlobalLogger.debug()
147 << DestinationEndpoint.address().to_string()
148 << ": cancel timer" << endl;
149 IcmpPacketReceiveTimer.cancel();
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150
151 GlobalLogger.debug()
152 << DestinationEndpoint.address().to_string()
d4e17c7a 153 << ": unregister" << endl;
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154
155 IcmpPingerItem icmp_item = boost::static_pointer_cast<IcmpPinger>( get_myself().lock() );
156 if ( icmp_item )
157 {
158 PacketDistributor->unregister_pinger( icmp_item );
159 } else
160 {
161 GlobalLogger.warning()
162 << DestinationEndpoint.address().to_string()
163 << ": weak pointer to pinger broken is empty. Huh?" << endl;
164 }
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165}
166
167
23f51766 168void IcmpPinger::set_destination_endpoint( const address &destination_ip )
39e10382 169{
39e10382 170 uint16_t port = 0;
23f51766 171 DestinationEndpoint = icmp::endpoint( destination_ip, port );
39e10382
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172}
173
ba5d41fe 174bool IcmpPinger::start_send()
4ea9706c 175{
83d87183 176 ++SequenceNumber;
5c670f6b 177
af68f845 178 IcmpPacketItem icmp_packet_echo_request = IcmpPacketFactory::create_icmp_packet_echo_request(
5b008ada 179 Protocol, Identifier, SequenceNumber );
83d87183 180
24e706c4 181 BOOST_ASSERT( PingerStatus == PingStatus_NotSent );
ba5d41fe 182 return send_echo_request( icmp_packet_echo_request );
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183}
184
ba5d41fe 185bool IcmpPinger::send_echo_request( const IcmpPacketItem icmp_packet )
a8d411d6 186{
cb60ed91 187 boost::asio::streambuf request_buffer;
a7c2eb51 188 ostream os( &request_buffer );
080ca508
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189 if ( !icmp_packet->write( os ) )
190 {
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191 GlobalLogger.error()
192 << DestinationEndpoint.address().to_string()
193 << ": fail writing ping data." << endl;
080ca508 194 }
cb60ed91 195
a7c2eb51 196 TimeSent = microsec_clock::universal_time();
040ffdf2 197
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198 string dest_address_string = DestinationEndpoint.address().to_string();
199 BOOST_ASSERT( !dest_address_string.empty() );
a4049623 200
822e4991 201 // Send the request
ba5d41fe 202 size_t bytes_sent = 0;
822e4991
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203 try
204 {
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205 GlobalLogger.info()
206 << DestinationEndpoint.address().to_string()
207 << ": sending ping" << endl;
822e4991 208 const_buffers_1 data = request_buffer.data();
747c13ca 209
39e10382 210 // Block until send the data
1ece191b 211 bytes_sent = PacketDistributor->get_socket()->send_to( data, DestinationEndpoint );
822e4991
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212 if ( bytes_sent != buffer_size( data ) )
213 {
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214 GlobalLogger.error()
215 << DestinationEndpoint.address().to_string()
216 << ": fail sending ping data." << endl;
822e4991
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217 }
218 }
219 catch ( const exception &ex )
a4049623 220 {
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221 GlobalLogger.error()
222 << DestinationEndpoint.address().to_string()
223 << ": fail sending ping data. " << ex.what() << endl;
a4049623 224 }
4ea9706c 225
e0a99ac4 226 ReplyReceived = false;
2210b856 227 schedule_timeout_echo_reply();
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228
229 return (bytes_sent > 0);
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230}
231
87e525ff 232void IcmpPinger::schedule_timeout_echo_reply()
2210b856
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233{
234 // Wait up to N seconds for a reply.
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235 (void) IcmpPacketReceiveTimer.expires_at(
236 TimeSent + seconds( EchoReplyTimeoutInSec )
237 );
238 IcmpPacketReceiveTimer.async_wait(
d26dce11 239 boost::bind( &IcmpPinger::handle_timeout, this, boost::asio::placeholders::error )
040ffdf2 240 );
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241}
242
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243/**
244 * @brief Gets called when the ping is finished: Either on timeout or on ping reply
245 *
246 * @return void
247 **/
d26dce11 248void IcmpPinger::handle_timeout(const boost::system::error_code& error)
bd1a2231 249{
d26dce11
CH
250 if (error)
251 {
252 if ( error == boost::asio::error::operation_aborted )
253 {
254 if (! ReplyReceived)
255 GlobalLogger.notice() << "Timer waiting for ICMP echo reply was cancelled!" << endl;
256 // otherwise probably called by IcmpPacketReceiveTimer.cancel in handle_receive_icmp_packet!
257 }
258 else
259 GlobalLogger.notice() << "Error " << error << " waiting for ICMP echo reply!" << endl;
260
261 // Still continue with rest of function, so PingStatus is updated and Callback executed
262 // when timer was cancelled
263 }
264
0697580f 265 // Check ReplyReceived as the timer handler
83e1eae2 266 // is also called by Timer.cancel();
080ca508 267 if ( !ReplyReceived )
bd1a2231 268 {
d9bbc1d7
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269 GlobalLogger.info()
270 << DestinationEndpoint.address().to_string()
271 << ": Request timed out" << endl;
bd1a2231
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272
273 set_ping_status( PingStatus_FailureTimeout );
274 }
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275
276 // Call ping-done handler
277 bool ping_success = (PingerStatus == PingStatus_SuccessReply);
0434b62a 278 PingDoneCallback( ping_success );
bd1a2231
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279}
280
bd1a2231 281
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282/**
283 * @brief Receive ICMP packets
c0950a05 284 * @param bytes_transferred Number of bytes transferred.
1ece191b 285 * @return true if packet matches a request from this pinger, false otherwise
49d66375 286 **/
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287bool IcmpPinger::handle_receive_icmp_packet(const IcmpPacketItem icmp_packet,
288 const size_t bytes_transferred )
4ea9706c 289{
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290 bool does_match = false;
291
d9bbc1d7 292 if ( ReplyReceived )
e0a99ac4 293 {
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294 // continue, might be an old packet
295 // or return false right away, do not want packet anyway...
7edd33cf 296 GlobalLogger.debug()
e0a99ac4
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297 << DestinationEndpoint.address().to_string()
298 << ": Not interested in packets since we already got a reply"
299 << endl;
300 return does_match;
301 }
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302
303 // We can receive all ICMP packets received by the host, so we need to
304 // filter out only the echo replies that match our identifier,
305 // expected sequence number, and destination host address (receive just
306 // the ICMP packets from the host we had ping).
307
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308 if ( icmp_packet->match_echo_reply(
309 Identifier, SequenceNumber,
310 DestinationEndpoint.address() ) )
d9bbc1d7
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311 {
312 GlobalLogger.info()
1ece191b
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313 << DestinationEndpoint.address().to_string()
314 << ": Received reply" << endl;
d9bbc1d7 315
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316 ReplyReceived = true;
317 does_match = true;
644e2ef7 318
c120ad42 319 icmp_packet->print( bytes_transferred, TimeSent );
c85c0309 320
1ece191b 321 set_ping_status( PingStatus_SuccessReply );
83d87183 322
e0a99ac4 323 IcmpPacketReceiveTimer.cancel(); //lint !e534
1ece191b
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324 }
325 else if ( icmp_packet->match_destination_unreachable(
326 Identifier, SequenceNumber,
327 DestinationEndpoint.address() ) )
328 {
329 GlobalLogger.info()
330 << DestinationEndpoint.address().to_string()
331 << ": Received destination unreachable" << endl;
d9bbc1d7 332
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333 ReplyReceived = true;
334 does_match = true;
644e2ef7 335
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336 icmp_packet->print( bytes_transferred, TimeSent );
337
338 set_ping_status( PingStatus_FailureDestinationUnreachable );
339
340 IcmpPacketReceiveTimer.cancel(); //lint !e534
341 }
342 else if ( icmp_packet->match_time_exceeded(
343 Identifier, SequenceNumber,
344 DestinationEndpoint.address() ) )
345 {
346 GlobalLogger.info()
347 << DestinationEndpoint.address().to_string()
348 << ": Received time exceeded" << endl;
349
350 ReplyReceived = true;
351 does_match = true;
352
c120ad42 353 icmp_packet->print( bytes_transferred, TimeSent );
49d66375 354
1ece191b 355 set_ping_status( PingStatus_FailureDestinationUnreachable );
2b5520bc 356
e0a99ac4 357 IcmpPacketReceiveTimer.cancel(); //lint !e534
d9a7f2f3 358 }
1ece191b 359 else
83e1eae2 360 {
7edd33cf 361 GlobalLogger.debug()
d9bbc1d7 362 << DestinationEndpoint.address().to_string()
7edd33cf
CH
363 << ": Received packet that does not match or has wrong seq.nr"
364 << endl;
2b5520bc 365 }
1ece191b
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366
367 return does_match;
f442d5f5
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368}
369
f5c0f0d0 370void IcmpPinger::set_ping_status( PingStatus ping_status )
83d87183
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371{
372 PingerStatus = ping_status;
373}
f076f8d4
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374
375//------------------------------------------------------------------------
376// IcmpPacketDistributor
377//------------------------------------------------------------------------
378
379static const std::size_t SOCKET_BUFFER_SIZE = 65536; // 64kB
380
381typedef std::set<IcmpPingerItem>::iterator PingerListIterator;
382
383
384bool IcmpPacketDistributor::InstanceIdentifierComparator::operator() (
385 const IcmpPacketDistributor::DistributorInstanceIdentifier &a,
386 const IcmpPacketDistributor::DistributorInstanceIdentifier &b )
387 const
388{
389 if ( a.first == boost::asio::ip::icmp::v4() )
390 {
391 if ( b.first == boost::asio::ip::icmp::v4() )
392 return a.second < b.second; // v4 == v4
393 else
394 BOOST_ASSERT( b.first == boost::asio::ip::icmp::v6() );
395 return true; // a(v4) < b(b6)
396 }
397 else
398 {
399 BOOST_ASSERT( a.first == boost::asio::ip::icmp::v6() );
400
401 if ( b.first == boost::asio::ip::icmp::v4() )
402 return false; // a(v6) > b(v4)
403 else
404 BOOST_ASSERT( b.first == boost::asio::ip::icmp::v6() );
405 return a.second < b.second; // v6 == v6
406 }
407}
408
409//-----------------------------------------------------------------------------
410// Definition of IcmpPacketDistributor
411//-----------------------------------------------------------------------------
412
413IcmpPacketDistributor::map_type IcmpPacketDistributor::Instances; // initialize
414
415
416IcmpPacketDistributorItem IcmpPacketDistributor::get_distributor(
417 const icmp::socket::protocol_type &protocol,
418 const std::string &network_interface,
419 const IoServiceItem io_serv )
420{
421 IcmpPacketDistributor::DistributorInstanceIdentifier identifier(
422 protocol, network_interface);
423
424 // check if there is an instance for this protocol and interface
425 if ( Instances.count(identifier) == 0 )
426 { // need to create an instance for this protocol and network interface
427 GlobalLogger.info() << "Creating IcmpPacketDistributor for interface "
428 << network_interface << std::endl;
429 IcmpPacketDistributorItem new_instance( new IcmpPacketDistributor(
430 protocol, network_interface, io_serv ) );
431 Instances[identifier] = new_instance;
432 }
433
434 BOOST_ASSERT( Instances.count(identifier) == 1 );
435
436 // return the one instance for this protocol and interface
437 return Instances[identifier];
438}
439
440
441IcmpPacketDistributorItem IcmpPacketDistributor::get_distributor(
442 const icmp::socket::protocol_type &protocol,
443 const std::string &network_interface )
444{
445 IcmpPacketDistributor::DistributorInstanceIdentifier identifier(
446 protocol, network_interface);
447
448 BOOST_ASSERT( Instances.count(identifier) == 1 );
449
450 // return the one instance for this protocol and interface
451 return Instances[identifier];
452}
453
454
455IcmpPacketDistributor::IcmpPacketDistributor(
456 const icmp::socket::protocol_type &protocol,
457 const std::string &network_interface,
458 const IoServiceItem io_serv ):
459 Protocol( protocol ),
e0a99ac4 460 Socket( new icmp::socket(*io_serv, protocol) ),
f076f8d4
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461 ReplyBuffer(),
462 PingerList()
463{
7edd33cf
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464 // set TTL for testing
465 //const boost::asio::ip::unicast::hops option( 3 );
466 //Socket->set_option(option);
467
f076f8d4
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468 NetworkInterface<icmp::socket, boost::asio::ip::icmp>
469 NetInterface( network_interface, *Socket );
470
471 if ( !NetInterface.bind() )
472 {
473 GlobalLogger.error()
474 << "Trouble creating IcmpPacketDistributor for interface "
475 << network_interface// << " and protocol " << protocol
476 << ": could not bind the socket with the local interface. "
477 << ::strerror( errno ) << std::endl;
478 }
479
480 register_receive_handler();
481}
482
483
484void IcmpPacketDistributor::register_receive_handler()
485{
486 // wait for reply, prepare buffer to receive up to SOCKET_BUFFER_SIZE bytes
487 Socket->async_receive(
488 ReplyBuffer.prepare( SOCKET_BUFFER_SIZE ),
489 boost::bind( &IcmpPacketDistributor::handle_receive, this,
490 boost::asio::placeholders::error,
491 boost::asio::placeholders::bytes_transferred )
492 );
493}
494
495void IcmpPacketDistributor::handle_receive(
496 const boost::system::error_code &error,
497 const size_t &bytes_transferred )
498{
499 if ( error )
500 {
501 GlobalLogger.warning()
502 << ": Received error " << error
503 << " in ICMP packet distributor; end handler and schedule another.";
504 register_receive_handler();
505 return;
506 }
507
508 // The actual number of bytes received is committed to the buffer so that we
509 // can extract it using a std::istream object.
510 ReplyBuffer.commit( bytes_transferred );
511
512 GlobalLogger.info() << "received packet in distributor" << std::endl;
513
e75a59e7
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514 std::istream is( &ReplyBuffer );
515 if ( !is )
f076f8d4 516 {
e75a59e7
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517 GlobalLogger.error() << "Can't handle ReplyBuffer" << std::endl;
518 return;
f076f8d4 519 }
e75a59e7
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520
521 // Decode the reply packet.
522 IcmpPacketItem icmp_packet = IcmpPacketFactory::create_icmp_packet(
523 Protocol, is );
524 if ( !icmp_packet )
7edd33cf 525 {
e75a59e7
CH
526 GlobalLogger.warning() << "Ignoring broken ICMP packet"
527 << std::endl;
7edd33cf 528 }
e75a59e7 529 else
f076f8d4 530 {
e75a59e7
CH
531 GlobalLogger.debug() << "Succesfully parsed ICMP packet"
532 << std::endl;
533
534 // check which pinger wants this packet
535 bool packet_matches = false;
536 BOOST_FOREACH( const IcmpPingerItem &pinger, PingerList )
537 {
538 packet_matches = pinger->handle_receive_icmp_packet(
539 icmp_packet, bytes_transferred);
540 if (packet_matches)
541 break;
542 }
543 if (!packet_matches)
544 GlobalLogger.info() << "Packet did not match any pinger"
545 << std::endl;
f076f8d4
CH
546 }
547
548 // re-register receive handler
549 register_receive_handler();
550}
551
552bool IcmpPacketDistributor::register_pinger( const IcmpPingerItem &new_pinger )
553{
554 std::pair<PingerListIterator, bool> result = PingerList.insert(new_pinger);
555 bool was_new = result.second;
556 if (was_new)
557 GlobalLogger.info() << "Register new pinger with IcmpPacketDistributor"
558 << std::endl;
559 else
560 GlobalLogger.warning()
561 << "Pinger to register was already known in IcmpPacketDistributor"
562 << std::endl;
563 return was_new;
564}
565
566
567bool IcmpPacketDistributor::unregister_pinger( const IcmpPingerItem &old_pinger )
568{
569 int n_erased = PingerList.erase(old_pinger);
570 bool was_erased = n_erased > 0;
571 if (was_erased)
572 GlobalLogger.info() << "Removed pinger from IcmpPacketDistributor"
573 << std::endl;
574 else
575 GlobalLogger.warning()
576 << "Could not find pinger to remove from IcmpPacketDistributor"
577 << std::endl;
578 return was_erased;
579}
580
581/**
582 * @brief for all instances: close sockets, unregister all pingers
583 */
584void IcmpPacketDistributor::clean_up_all()
585{
586 BOOST_FOREACH( IcmpPacketDistributor::map_type::value_type &instance,
587 Instances )
1ea5fa63 588 {
f076f8d4 589 instance.second->clean_up();
1ea5fa63 590 }
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CH
591
592 Instances.clear();
593}
594
595void IcmpPacketDistributor::clean_up()
596{
597 if (PingerList.size() > 0)
598 GlobalLogger.warning() << "There were still " << PingerList.size()
599 << " pingers registered in IcmpPacketDistributor!" << std::endl;
600 PingerList.clear();
601
602 boost::system::error_code error;
603 //Socket->shutdown(icmp::socket::shutdown_both, error); //both=send&receive
604 //if ( error )
605 // GlobalLogger.warning() << "Received error " << error
606 // << " when shutting down ICMP socket";
607 // always gave an error system:9 (probably EBADF: Bad file descriptor)
608
609 Socket->close(error);
610 if ( error )
611 GlobalLogger.warning() << "Received error " << error
612 << " when closing ICMP socket";
613}
614
615IcmpPacketDistributor::~IcmpPacketDistributor()
616{
617 GlobalLogger.info() << "Destroying IcmpPacketDistributor" << std::endl;
618}
619
620SocketItem IcmpPacketDistributor::get_socket() const
621{
622 return Socket;
623}