aboutsummaryrefslogtreecommitdiff
path: root/src/banman.cpp
blob: 3cd646c148daa56bf0eedaed85adc0c09de9537f (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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2021 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include <banman.h>

#include <netaddress.h>
#include <node/interface_ui.h>
#include <sync.h>
#include <util/system.h>
#include <util/time.h>
#include <util/translation.h>


BanMan::BanMan(fs::path ban_file, CClientUIInterface* client_interface, int64_t default_ban_time)
    : m_client_interface(client_interface), m_ban_db(std::move(ban_file)), m_default_ban_time(default_ban_time)
{
    LoadBanlist();
    DumpBanlist();
}

BanMan::~BanMan()
{
    DumpBanlist();
}

void BanMan::LoadBanlist()
{
    LOCK(m_cs_banned);

    if (m_client_interface) m_client_interface->InitMessage(_("Loading banlist…").translated);

    const auto start{SteadyClock::now()};
    if (m_ban_db.Read(m_banned)) {
        SweepBanned(); // sweep out unused entries

        LogPrint(BCLog::NET, "Loaded %d banned node addresses/subnets  %dms\n", m_banned.size(),
                 Ticks<std::chrono::milliseconds>(SteadyClock::now() - start));
    } else {
        LogPrintf("Recreating the banlist database\n");
        m_banned = {};
        m_is_dirty = true;
    }
}

void BanMan::DumpBanlist()
{
    static Mutex dump_mutex;
    LOCK(dump_mutex);

    banmap_t banmap;
    {
        LOCK(m_cs_banned);
        SweepBanned();
        if (!BannedSetIsDirty()) return;
        banmap = m_banned;
        SetBannedSetDirty(false);
    }

    const auto start{SteadyClock::now()};
    if (!m_ban_db.Write(banmap)) {
        SetBannedSetDirty(true);
    }

    LogPrint(BCLog::NET, "Flushed %d banned node addresses/subnets to disk  %dms\n", banmap.size(),
             Ticks<std::chrono::milliseconds>(SteadyClock::now() - start));
}

void BanMan::ClearBanned()
{
    {
        LOCK(m_cs_banned);
        m_banned.clear();
        m_is_dirty = true;
    }
    DumpBanlist(); //store banlist to disk
    if (m_client_interface) m_client_interface->BannedListChanged();
}

bool BanMan::IsDiscouraged(const CNetAddr& net_addr)
{
    LOCK(m_cs_banned);
    return m_discouraged.contains(net_addr.GetAddrBytes());
}

bool BanMan::IsBanned(const CNetAddr& net_addr)
{
    auto current_time = GetTime();
    LOCK(m_cs_banned);
    for (const auto& it : m_banned) {
        CSubNet sub_net = it.first;
        CBanEntry ban_entry = it.second;

        if (current_time < ban_entry.nBanUntil && sub_net.Match(net_addr)) {
            return true;
        }
    }
    return false;
}

bool BanMan::IsBanned(const CSubNet& sub_net)
{
    auto current_time = GetTime();
    LOCK(m_cs_banned);
    banmap_t::iterator i = m_banned.find(sub_net);
    if (i != m_banned.end()) {
        CBanEntry ban_entry = (*i).second;
        if (current_time < ban_entry.nBanUntil) {
            return true;
        }
    }
    return false;
}

void BanMan::Ban(const CNetAddr& net_addr, int64_t ban_time_offset, bool since_unix_epoch)
{
    CSubNet sub_net(net_addr);
    Ban(sub_net, ban_time_offset, since_unix_epoch);
}

void BanMan::Discourage(const CNetAddr& net_addr)
{
    LOCK(m_cs_banned);
    m_discouraged.insert(net_addr.GetAddrBytes());
}

void BanMan::Ban(const CSubNet& sub_net, int64_t ban_time_offset, bool since_unix_epoch)
{
    CBanEntry ban_entry(GetTime());

    int64_t normalized_ban_time_offset = ban_time_offset;
    bool normalized_since_unix_epoch = since_unix_epoch;
    if (ban_time_offset <= 0) {
        normalized_ban_time_offset = m_default_ban_time;
        normalized_since_unix_epoch = false;
    }
    ban_entry.nBanUntil = (normalized_since_unix_epoch ? 0 : GetTime()) + normalized_ban_time_offset;

    {
        LOCK(m_cs_banned);
        if (m_banned[sub_net].nBanUntil < ban_entry.nBanUntil) {
            m_banned[sub_net] = ban_entry;
            m_is_dirty = true;
        } else
            return;
    }
    if (m_client_interface) m_client_interface->BannedListChanged();

    //store banlist to disk immediately
    DumpBanlist();
}

bool BanMan::Unban(const CNetAddr& net_addr)
{
    CSubNet sub_net(net_addr);
    return Unban(sub_net);
}

bool BanMan::Unban(const CSubNet& sub_net)
{
    {
        LOCK(m_cs_banned);
        if (m_banned.erase(sub_net) == 0) return false;
        m_is_dirty = true;
    }
    if (m_client_interface) m_client_interface->BannedListChanged();
    DumpBanlist(); //store banlist to disk immediately
    return true;
}

void BanMan::GetBanned(banmap_t& banmap)
{
    LOCK(m_cs_banned);
    // Sweep the banlist so expired bans are not returned
    SweepBanned();
    banmap = m_banned; //create a thread safe copy
}

void BanMan::SweepBanned()
{
    AssertLockHeld(m_cs_banned);

    int64_t now = GetTime();
    bool notify_ui = false;
    banmap_t::iterator it = m_banned.begin();
    while (it != m_banned.end()) {
        CSubNet sub_net = (*it).first;
        CBanEntry ban_entry = (*it).second;
        if (!sub_net.IsValid() || now > ban_entry.nBanUntil) {
            m_banned.erase(it++);
            m_is_dirty = true;
            notify_ui = true;
            LogPrint(BCLog::NET, "Removed banned node address/subnet: %s\n", sub_net.ToString());
        } else {
            ++it;
        }
    }

    // update UI
    if (notify_ui && m_client_interface) {
        m_client_interface->BannedListChanged();
    }
}

bool BanMan::BannedSetIsDirty()
{
    LOCK(m_cs_banned);
    return m_is_dirty;
}

void BanMan::SetBannedSetDirty(bool dirty)
{
    LOCK(m_cs_banned); //reuse m_banned lock for the m_is_dirty flag
    m_is_dirty = dirty;
}