1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2019 The Bitcoin Core developers
3 // Distributed under the MIT software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5
6 #include <banman.h>
7
8 #include <netaddress.h>
9 #include <ui_interface.h>
10 #include <util/system.h>
11 #include <util/time.h>
12 #include <util/translation.h>
13
14
BanMan(fs::path ban_file,CClientUIInterface * client_interface,int64_t default_ban_time)15 BanMan::BanMan(fs::path ban_file, CClientUIInterface* client_interface, int64_t default_ban_time)
16 : m_client_interface(client_interface), m_ban_db(std::move(ban_file)), m_default_ban_time(default_ban_time)
17 {
18 if (m_client_interface) m_client_interface->InitMessage(_("Loading banlist...").translated);
19
20 int64_t n_start = GetTimeMillis();
21 m_is_dirty = false;
22 banmap_t banmap;
23 if (m_ban_db.Read(banmap)) {
24 SetBanned(banmap); // thread save setter
25 SetBannedSetDirty(false); // no need to write down, just read data
26 SweepBanned(); // sweep out unused entries
27
28 LogPrint(BCLog::NET, "Loaded %d banned node ips/subnets from banlist.dat %dms\n",
29 banmap.size(), GetTimeMillis() - n_start);
30 } else {
31 LogPrintf("Invalid or missing banlist.dat; recreating\n");
32 SetBannedSetDirty(true); // force write
33 DumpBanlist();
34 }
35 }
36
~BanMan()37 BanMan::~BanMan()
38 {
39 DumpBanlist();
40 }
41
DumpBanlist()42 void BanMan::DumpBanlist()
43 {
44 SweepBanned(); // clean unused entries (if bantime has expired)
45
46 if (!BannedSetIsDirty()) return;
47
48 int64_t n_start = GetTimeMillis();
49
50 banmap_t banmap;
51 GetBanned(banmap);
52 if (m_ban_db.Write(banmap)) {
53 SetBannedSetDirty(false);
54 }
55
56 LogPrint(BCLog::NET, "Flushed %d banned node ips/subnets to banlist.dat %dms\n",
57 banmap.size(), GetTimeMillis() - n_start);
58 }
59
ClearBanned()60 void BanMan::ClearBanned()
61 {
62 {
63 LOCK(m_cs_banned);
64 m_banned.clear();
65 m_is_dirty = true;
66 }
67 DumpBanlist(); //store banlist to disk
68 if (m_client_interface) m_client_interface->BannedListChanged();
69 }
70
IsDiscouraged(const CNetAddr & net_addr)71 bool BanMan::IsDiscouraged(const CNetAddr& net_addr)
72 {
73 LOCK(m_cs_banned);
74 return m_discouraged.contains(net_addr.GetAddrBytes());
75 }
76
IsBanned(const CNetAddr & net_addr)77 bool BanMan::IsBanned(const CNetAddr& net_addr)
78 {
79 auto current_time = GetTime();
80 LOCK(m_cs_banned);
81 for (const auto& it : m_banned) {
82 CSubNet sub_net = it.first;
83 CBanEntry ban_entry = it.second;
84
85 if (current_time < ban_entry.nBanUntil && sub_net.Match(net_addr)) {
86 return true;
87 }
88 }
89 return false;
90 }
91
IsBanned(const CSubNet & sub_net)92 bool BanMan::IsBanned(const CSubNet& sub_net)
93 {
94 auto current_time = GetTime();
95 LOCK(m_cs_banned);
96 banmap_t::iterator i = m_banned.find(sub_net);
97 if (i != m_banned.end()) {
98 CBanEntry ban_entry = (*i).second;
99 if (current_time < ban_entry.nBanUntil) {
100 return true;
101 }
102 }
103 return false;
104 }
105
Ban(const CNetAddr & net_addr,int64_t ban_time_offset,bool since_unix_epoch)106 void BanMan::Ban(const CNetAddr& net_addr, int64_t ban_time_offset, bool since_unix_epoch)
107 {
108 CSubNet sub_net(net_addr);
109 Ban(sub_net, ban_time_offset, since_unix_epoch);
110 }
111
Discourage(const CNetAddr & net_addr)112 void BanMan::Discourage(const CNetAddr& net_addr)
113 {
114 LOCK(m_cs_banned);
115 m_discouraged.insert(net_addr.GetAddrBytes());
116 }
117
Ban(const CSubNet & sub_net,int64_t ban_time_offset,bool since_unix_epoch)118 void BanMan::Ban(const CSubNet& sub_net, int64_t ban_time_offset, bool since_unix_epoch)
119 {
120 CBanEntry ban_entry(GetTime());
121
122 int64_t normalized_ban_time_offset = ban_time_offset;
123 bool normalized_since_unix_epoch = since_unix_epoch;
124 if (ban_time_offset <= 0) {
125 normalized_ban_time_offset = m_default_ban_time;
126 normalized_since_unix_epoch = false;
127 }
128 ban_entry.nBanUntil = (normalized_since_unix_epoch ? 0 : GetTime()) + normalized_ban_time_offset;
129
130 {
131 LOCK(m_cs_banned);
132 if (m_banned[sub_net].nBanUntil < ban_entry.nBanUntil) {
133 m_banned[sub_net] = ban_entry;
134 m_is_dirty = true;
135 } else
136 return;
137 }
138 if (m_client_interface) m_client_interface->BannedListChanged();
139
140 //store banlist to disk immediately
141 DumpBanlist();
142 }
143
Unban(const CNetAddr & net_addr)144 bool BanMan::Unban(const CNetAddr& net_addr)
145 {
146 CSubNet sub_net(net_addr);
147 return Unban(sub_net);
148 }
149
Unban(const CSubNet & sub_net)150 bool BanMan::Unban(const CSubNet& sub_net)
151 {
152 {
153 LOCK(m_cs_banned);
154 if (m_banned.erase(sub_net) == 0) return false;
155 m_is_dirty = true;
156 }
157 if (m_client_interface) m_client_interface->BannedListChanged();
158 DumpBanlist(); //store banlist to disk immediately
159 return true;
160 }
161
GetBanned(banmap_t & banmap)162 void BanMan::GetBanned(banmap_t& banmap)
163 {
164 LOCK(m_cs_banned);
165 // Sweep the banlist so expired bans are not returned
166 SweepBanned();
167 banmap = m_banned; //create a thread safe copy
168 }
169
SetBanned(const banmap_t & banmap)170 void BanMan::SetBanned(const banmap_t& banmap)
171 {
172 LOCK(m_cs_banned);
173 m_banned = banmap;
174 m_is_dirty = true;
175 }
176
SweepBanned()177 void BanMan::SweepBanned()
178 {
179 int64_t now = GetTime();
180 bool notify_ui = false;
181 {
182 LOCK(m_cs_banned);
183 banmap_t::iterator it = m_banned.begin();
184 while (it != m_banned.end()) {
185 CSubNet sub_net = (*it).first;
186 CBanEntry ban_entry = (*it).second;
187 if (now > ban_entry.nBanUntil) {
188 m_banned.erase(it++);
189 m_is_dirty = true;
190 notify_ui = true;
191 LogPrint(BCLog::NET, "%s: Removed banned node ip/subnet from banlist.dat: %s\n", __func__, sub_net.ToString());
192 } else
193 ++it;
194 }
195 }
196 // update UI
197 if (notify_ui && m_client_interface) {
198 m_client_interface->BannedListChanged();
199 }
200 }
201
BannedSetIsDirty()202 bool BanMan::BannedSetIsDirty()
203 {
204 LOCK(m_cs_banned);
205 return m_is_dirty;
206 }
207
SetBannedSetDirty(bool dirty)208 void BanMan::SetBannedSetDirty(bool dirty)
209 {
210 LOCK(m_cs_banned); //reuse m_banned lock for the m_is_dirty flag
211 m_is_dirty = dirty;
212 }
213