summaryrefslogtreecommitdiff
path: root/src/DHTRoutingTableDeserializer.cc
blob: 48b8a2fbf3adabd642aeaab933fbd5af0caba2d5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/* <!-- copyright */
/*
 * aria2 - The high speed download utility
 *
 * Copyright (C) 2006 Tatsuhiro Tsujikawa
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link the code of portions of this program with the
 * OpenSSL library under certain conditions as described in each
 * individual source file, and distribute linked combinations
 * including the two.
 * You must obey the GNU General Public License in all respects
 * for all of the code used other than OpenSSL.  If you modify
 * file(s) with this exception, you may extend this exception to your
 * version of the file(s), but you are not obligated to do so.  If you
 * do not wish to do so, delete this exception statement from your
 * version.  If you delete this exception statement from all source
 * files in the program, then also delete it here.
 */
/* copyright --> */
#include "DHTRoutingTableDeserializer.h"
#include "DHTNode.h"
#include "DHTConstants.h"
#include "PeerMessageUtil.h"
#include "DlAbortEx.h"
#include "Logger.h"
#include "a2netcompat.h"
#include "StringFormat.h"
#include "Util.h"
#include <cerrno>
#include <cstring>
#include <istream>
#include <utility>

namespace aria2 {

DHTRoutingTableDeserializer::DHTRoutingTableDeserializer() {}

DHTRoutingTableDeserializer::~DHTRoutingTableDeserializer() {}

SharedHandle<DHTNode> DHTRoutingTableDeserializer::getLocalNode() const
{
  return _localNode;
}

const std::deque<SharedHandle<DHTNode> >& DHTRoutingTableDeserializer::getNodes() const
{
  return _nodes;
}

void DHTRoutingTableDeserializer::deserialize(std::istream& in)
{
  try {
    char header[8];
    memset(header, 0, sizeof(header));
    // magic
    header[0] = 0xa1;
    header[1] = 0xa2;
    // format ID
    header[2] = 0x02;
    // version
    header[6] = 0;
    header[7] = 0x03;

    char headerCompat[8];
    memset(headerCompat, 0, sizeof(headerCompat));
    // magic
    headerCompat[0] = 0xa1;
    headerCompat[1] = 0xa2;
    // format ID
    headerCompat[2] = 0x02;
    // version
    headerCompat[6] = 0;
    headerCompat[7] = 0x02;

    char zero[8];
    memset(zero, 0, sizeof(zero));

    int version;
    char buf[26];
    // header
    in.read(buf, 8);
    if(memcmp(header, buf, 8) == 0) {
      version = 3;
    } else if(memcmp(headerCompat, buf, 8) == 0) {
      version = 2;
    } else {
      throw DlAbortEx
	(StringFormat("Failed to load DHT routing table. cause:%s",
		      "bad header").str());
    }
    // time
    if(version == 2) {
      in.read(buf, 4);
      _serializedTime.setTimeInSec(ntohl(*reinterpret_cast<uint32_t*>(buf)));
      // 4bytes reserved
      in.read(buf, 4);
    } else {
      in.read(buf, 8);
      _serializedTime.setTimeInSec(ntoh64(*reinterpret_cast<uint64_t*>(buf)));
    }
  
    // localnode
    // 8bytes reserved
    in.read(buf, 8);
    // localnode ID
    in.read(buf, DHT_ID_LENGTH);
    SharedHandle<DHTNode> localNode(new DHTNode(reinterpret_cast<const unsigned char*>(buf)));
    // 4bytes reserved
    in.read(buf, 4);

    // number of nodes
    in.read(buf, 4);
    uint32_t numNodes = ntohl(*reinterpret_cast<uint32_t*>(buf));
    // 4bytes reserved
    in.read(buf, 4);

    // nodes
    for(size_t i = 0; i < numNodes; ++i) {
      // Currently, only IPv4 addresses are supported.
      // 1byte compact peer info length
      uint8_t peerInfoLen;
      in >> peerInfoLen;
      if(peerInfoLen != 6) {
	// skip this entry
	in.read(buf, 42+7+6);
	continue;
      }
      // 7bytes reserved
      in.read(buf, 7);
      // 6bytes compact peer info
      in.read(buf, 6);
      if(memcmp(zero, buf, 6) == 0) {
	// skip this entry
	in.read(buf, 42);
	continue;
      }
      std::pair<std::string, uint16_t> peer =
	PeerMessageUtil::unpackcompact(reinterpret_cast<const unsigned char*>(buf));
      if(peer.first.empty()) {
	// skip this entry
	in.read(buf, 42);
	continue;
      }
      // 2bytes reserved
      in.read(buf, 2);
      // 16byte reserved
      in.read(buf, 16);
      // localnode ID
      in.read(buf, DHT_ID_LENGTH);

      SharedHandle<DHTNode> node(new DHTNode(reinterpret_cast<const unsigned char*>(buf)));
      node->setIPAddress(peer.first);
      node->setPort(peer.second);
      // 4bytes reserved
      in.read(buf, 4);

      _nodes.push_back(node);
    }
    _localNode = localNode;
  } catch(std::ios::failure const& exception) {
    _nodes.clear();
    throw DlAbortEx
      (StringFormat("Failed to load DHT routing table. cause:%s",
		    strerror(errno)).str());
  }
}

} // namespace aria2