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-rw-r--r--modules/m_dns.cpp1126
1 files changed, 0 insertions, 1126 deletions
diff --git a/modules/m_dns.cpp b/modules/m_dns.cpp
deleted file mode 100644
index a75ca6820..000000000
--- a/modules/m_dns.cpp
+++ /dev/null
@@ -1,1126 +0,0 @@
-/*
- *
- * (C) 2003-2024 Anope Team
- * Contact us at team@anope.org
- *
- * Please read COPYING and README for further details.
- *
- * Based on the original code of Epona by Lara.
- * Based on the original code of Services by Andy Church.
- */
-
-#include "module.h"
-#include "modules/dns.h"
-
-using namespace DNS;
-
-namespace
-{
- Anope::string admin, nameservers;
- int refresh;
- time_t timeout;
-}
-
-/** A full packet sent or received to/from the nameserver
- */
-class Packet final
- : public Query
-{
- static bool IsValidName(const Anope::string &name)
- {
- return name.find_first_not_of("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ.-") == Anope::string::npos;
- }
-
- void PackName(unsigned char *output, unsigned short output_size, unsigned short &pos, const Anope::string &name)
- {
- if (pos + name.length() + 2 > output_size)
- throw SocketException("Unable to pack name");
-
- Log(LOG_DEBUG_2) << "Resolver: PackName packing " << name;
-
- sepstream sep(name, '.');
- Anope::string token;
-
- while (sep.GetToken(token))
- {
- output[pos++] = token.length();
- memcpy(&output[pos], token.c_str(), token.length());
- pos += token.length();
- }
-
- output[pos++] = 0;
- }
-
- Anope::string UnpackName(const unsigned char *input, unsigned short input_size, unsigned short &pos)
- {
- Anope::string name;
- unsigned short pos_ptr = pos, lowest_ptr = input_size;
- bool compressed = false;
-
- if (pos_ptr >= input_size)
- throw SocketException("Unable to unpack name - no input");
-
- while (input[pos_ptr] > 0)
- {
- unsigned short offset = input[pos_ptr];
-
- if (offset & POINTER)
- {
- if ((offset & POINTER) != POINTER)
- throw SocketException("Unable to unpack name - bogus compression header");
- if (pos_ptr + 1 >= input_size)
- throw SocketException("Unable to unpack name - bogus compression header");
-
- /* Place pos at the second byte of the first (farthest) compression pointer */
- if (compressed == false)
- {
- ++pos;
- compressed = true;
- }
-
- pos_ptr = (offset & LABEL) << 8 | input[pos_ptr + 1];
-
- /* Pointers can only go back */
- if (pos_ptr >= lowest_ptr)
- throw SocketException("Unable to unpack name - bogus compression pointer");
- lowest_ptr = pos_ptr;
- }
- else
- {
- if (pos_ptr + offset + 1 >= input_size)
- throw SocketException("Unable to unpack name - offset too large");
- if (!name.empty())
- name += ".";
- for (unsigned i = 1; i <= offset; ++i)
- name += input[pos_ptr + i];
-
- pos_ptr += offset + 1;
- if (compressed == false)
- /* Move up pos */
- pos = pos_ptr;
- }
- }
-
- /* +1 pos either to one byte after the compression pointer or one byte after the ending \0 */
- ++pos;
-
- /* Empty names are valid (root domain) */
-
- Log(LOG_DEBUG_2) << "Resolver: UnpackName successfully unpacked " << name;
-
- return name;
- }
-
- Question UnpackQuestion(const unsigned char *input, unsigned short input_size, unsigned short &pos)
- {
- Question question;
-
- question.name = this->UnpackName(input, input_size, pos);
-
- if (pos + 4 > input_size)
- throw SocketException("Unable to unpack question");
-
- if (!IsValidName(question.name))
- throw SocketException("Invalid question name");
-
- question.type = static_cast<QueryType>(input[pos] << 8 | input[pos + 1]);
- pos += 2;
-
- question.qclass = input[pos] << 8 | input[pos + 1];
- pos += 2;
-
- return question;
- }
-
- ResourceRecord UnpackResourceRecord(const unsigned char *input, unsigned short input_size, unsigned short &pos)
- {
- ResourceRecord record = static_cast<ResourceRecord>(this->UnpackQuestion(input, input_size, pos));
-
- if (pos + 6 > input_size)
- throw SocketException("Unable to unpack resource record");
-
- record.ttl = (input[pos] << 24) | (input[pos + 1] << 16) | (input[pos + 2] << 8) | input[pos + 3];
- pos += 4;
-
- //record.rdlength = input[pos] << 8 | input[pos + 1];
- pos += 2;
-
- switch (record.type)
- {
- case QUERY_A:
- {
- if (pos + 4 > input_size)
- throw SocketException("Unable to unpack resource record");
-
- in_addr a;
- a.s_addr = input[pos] | (input[pos + 1] << 8) | (input[pos + 2] << 16) | (input[pos + 3] << 24);
- pos += 4;
-
- sockaddrs addrs;
- addrs.ntop(AF_INET, &a);
- if (!addrs.valid())
- throw SocketException("Invalid IP");
-
- record.rdata = addrs.addr();
- break;
- }
- case QUERY_AAAA:
- {
- if (pos + 16 > input_size)
- throw SocketException("Unable to unpack resource record");
-
- in6_addr a;
- for (int j = 0; j < 16; ++j)
- a.s6_addr[j] = input[pos + j];
- pos += 16;
-
- sockaddrs addrs;
- addrs.ntop(AF_INET6, &a);
- if (!addrs.valid())
- throw SocketException("Invalid IP");
-
- record.rdata = addrs.addr();
- break;
- }
- case QUERY_CNAME:
- case QUERY_PTR:
- {
- record.rdata = this->UnpackName(input, input_size, pos);
-
- if (!IsValidName(record.rdata))
- throw SocketException("Invalid cname/ptr record data");
-
- break;
- }
- default:
- break;
- }
-
- Log(LOG_DEBUG_2) << "Resolver: " << record.name << " -> " << record.rdata;
-
- return record;
- }
-
-public:
- static const int POINTER = 0xC0;
- static const int LABEL = 0x3F;
- static const int HEADER_LENGTH = 12;
-
- Manager *manager;
- /* Source or destination of the packet */
- sockaddrs addr;
- /* ID for this packet */
- unsigned short id = 0;
- /* Flags on the packet */
- unsigned short flags = 0;
-
- Packet(Manager *m, sockaddrs *a) : manager(m)
- {
- if (a)
- addr = *a;
- }
-
- void Fill(const unsigned char *input, const unsigned short len)
- {
- if (len < HEADER_LENGTH)
- throw SocketException("Unable to fill packet");
-
- unsigned short packet_pos = 0;
-
- this->id = (input[packet_pos] << 8) | input[packet_pos + 1];
- packet_pos += 2;
-
- this->flags = (input[packet_pos] << 8) | input[packet_pos + 1];
- packet_pos += 2;
-
- unsigned short qdcount = (input[packet_pos] << 8) | input[packet_pos + 1];
- packet_pos += 2;
-
- unsigned short ancount = (input[packet_pos] << 8) | input[packet_pos + 1];
- packet_pos += 2;
-
- unsigned short nscount = (input[packet_pos] << 8) | input[packet_pos + 1];
- packet_pos += 2;
-
- unsigned short arcount = (input[packet_pos] << 8) | input[packet_pos + 1];
- packet_pos += 2;
-
- Log(LOG_DEBUG_2) << "Resolver: qdcount: " << qdcount << " ancount: " << ancount << " nscount: " << nscount << " arcount: " << arcount;
-
- for (unsigned i = 0; i < qdcount; ++i)
- this->questions.push_back(this->UnpackQuestion(input, len, packet_pos));
-
- for (unsigned i = 0; i < ancount; ++i)
- this->answers.push_back(this->UnpackResourceRecord(input, len, packet_pos));
-
- try
- {
- for (unsigned i = 0; i < nscount; ++i)
- this->authorities.push_back(this->UnpackResourceRecord(input, len, packet_pos));
-
- for (unsigned i = 0; i < arcount; ++i)
- this->additional.push_back(this->UnpackResourceRecord(input, len, packet_pos));
- }
- catch (const SocketException &ex)
- {
- Log(LOG_DEBUG_2) << "Unable to parse ns/ar records: " << ex.GetReason();
- }
- }
-
- unsigned short Pack(unsigned char *output, unsigned short output_size)
- {
- if (output_size < HEADER_LENGTH)
- throw SocketException("Unable to pack packet");
-
- unsigned short pos = 0;
-
- output[pos++] = this->id >> 8;
- output[pos++] = this->id & 0xFF;
- output[pos++] = this->flags >> 8;
- output[pos++] = this->flags & 0xFF;
- output[pos++] = this->questions.size() >> 8;
- output[pos++] = this->questions.size() & 0xFF;
- output[pos++] = this->answers.size() >> 8;
- output[pos++] = this->answers.size() & 0xFF;
- output[pos++] = this->authorities.size() >> 8;
- output[pos++] = this->authorities.size() & 0xFF;
- output[pos++] = this->additional.size() >> 8;
- output[pos++] = this->additional.size() & 0xFF;
-
- for (auto &q : this->questions)
- {
- if (q.type == QUERY_PTR)
- {
- sockaddrs ip(q.name);
- if (!ip.valid())
- throw SocketException("Invalid IP");
-
- switch (ip.family())
- {
- case AF_INET6:
- q.name = ip.reverse() + ".ip6.arpa";
- break;
- case AF_INET:
- q.name = ip.reverse() + ".in-addr.arpa";
- break;
- default:
- throw SocketException("Unsupported IP Family");
- }
- }
-
- this->PackName(output, output_size, pos, q.name);
-
- if (pos + 4 >= output_size)
- throw SocketException("Unable to pack packet");
-
- short s = htons(q.type);
- memcpy(&output[pos], &s, 2);
- pos += 2;
-
- s = htons(q.qclass);
- memcpy(&output[pos], &s, 2);
- pos += 2;
- }
-
- std::vector<ResourceRecord> types[] = { this->answers, this->authorities, this->additional };
- for (auto &type : types)
- {
- for (const auto &rr : type)
- {
- this->PackName(output, output_size, pos, rr.name);
-
- if (pos + 8 >= output_size)
- throw SocketException("Unable to pack packet");
-
- short s = htons(rr.type);
- memcpy(&output[pos], &s, 2);
- pos += 2;
-
- s = htons(rr.qclass);
- memcpy(&output[pos], &s, 2);
- pos += 2;
-
- long l = htonl(rr.ttl);
- memcpy(&output[pos], &l, 4);
- pos += 4;
-
- switch (rr.type)
- {
- case QUERY_A:
- {
- if (pos + 6 > output_size)
- throw SocketException("Unable to pack packet");
-
- sockaddrs a(rr.rdata);
- if (!a.valid())
- throw SocketException("Invalid IP");
-
- s = htons(4);
- memcpy(&output[pos], &s, 2);
- pos += 2;
-
- memcpy(&output[pos], &a.sa4.sin_addr, 4);
- pos += 4;
- break;
- }
- case QUERY_AAAA:
- {
- if (pos + 18 > output_size)
- throw SocketException("Unable to pack packet");
-
- sockaddrs a(rr.rdata);
- if (!a.valid())
- throw SocketException("Invalid IP");
-
- s = htons(16);
- memcpy(&output[pos], &s, 2);
- pos += 2;
-
- memcpy(&output[pos], &a.sa6.sin6_addr, 16);
- pos += 16;
- break;
- }
- case QUERY_NS:
- case QUERY_CNAME:
- case QUERY_PTR:
- {
- if (pos + 2 >= output_size)
- throw SocketException("Unable to pack packet");
-
- unsigned short packet_pos_save = pos;
- pos += 2;
-
- this->PackName(output, output_size, pos, rr.rdata);
-
- s = htons(pos - packet_pos_save - 2);
- memcpy(&output[packet_pos_save], &s, 2);
- break;
- }
- case QUERY_SOA:
- {
- if (pos + 2 >= output_size)
- throw SocketException("Unable to pack packet");
-
- unsigned short packet_pos_save = pos;
- pos += 2;
-
- std::vector<Anope::string> ns;
- spacesepstream(nameservers).GetTokens(ns);
- this->PackName(output, output_size, pos, !ns.empty() ? ns[0] : "");
- this->PackName(output, output_size, pos, admin.replace_all_cs('@', '.'));
-
- if (pos + 20 >= output_size)
- throw SocketException("Unable to pack SOA");
-
- l = htonl(manager->GetSerial());
- memcpy(&output[pos], &l, 4);
- pos += 4;
-
- l = htonl(refresh); // Refresh
- memcpy(&output[pos], &l, 4);
- pos += 4;
-
- l = htonl(refresh); // Retry
- memcpy(&output[pos], &l, 4);
- pos += 4;
-
- l = htonl(604800); // Expire
- memcpy(&output[pos], &l, 4);
- pos += 4;
-
- l = htonl(0); // Minimum
- memcpy(&output[pos], &l, 4);
- pos += 4;
-
- s = htons(pos - packet_pos_save - 2);
- memcpy(&output[packet_pos_save], &s, 2);
-
- break;
- }
- default:
- break;
- }
- }
- }
-
- return pos;
- }
-};
-
-namespace DNS
-{
- class ReplySocket
- : public virtual Socket
- {
- public:
- ~ReplySocket() override = default;
- virtual void Reply(Packet *p) = 0;
- };
-}
-
-/* Listens for TCP requests */
-class TCPSocket final
- : public ListenSocket
-{
- Manager *manager;
-
-public:
- /* A TCP client */
- class Client final
- : public ClientSocket
- , public Timer
- , public ReplySocket
- {
- Manager *manager;
- Packet *packet = nullptr;
- unsigned char packet_buffer[524];
- int length = 0;
-
- public:
- Client(Manager *m, TCPSocket *l, int fd, const sockaddrs &addr) : Socket(fd, l->GetFamily()), ClientSocket(l, addr), Timer(5),
- manager(m)
- {
- Log(LOG_DEBUG_2) << "Resolver: New client from " << addr.addr();
- }
-
- ~Client() override
- {
- Log(LOG_DEBUG_2) << "Resolver: Exiting client from " << clientaddr.addr();
- delete packet;
- }
-
- /* Times out after a few seconds */
- void Tick(time_t) override { }
-
- void Reply(Packet *p) override
- {
- delete packet;
- packet = p;
- SocketEngine::Change(this, true, SF_WRITABLE);
- }
-
- bool ProcessRead() override
- {
- Log(LOG_DEBUG_2) << "Resolver: Reading from DNS TCP socket";
-
- int i = recv(this->GetFD(), reinterpret_cast<char *>(packet_buffer) + length, sizeof(packet_buffer) - length, 0);
- if (i <= 0)
- return false;
-
- length += i;
-
- unsigned short want_len = packet_buffer[0] << 8 | packet_buffer[1];
- if (length >= want_len + 2)
- {
- int len = length - 2;
- length -= want_len + 2;
- return this->manager->HandlePacket(this, packet_buffer + 2, len, NULL);
- }
- return true;
- }
-
- bool ProcessWrite() override
- {
- Log(LOG_DEBUG_2) << "Resolver: Writing to DNS TCP socket";
-
- if (packet != NULL)
- {
- try
- {
- unsigned char buffer[65535];
- unsigned short len = packet->Pack(buffer + 2, sizeof(buffer) - 2);
-
- short s = htons(len);
- memcpy(buffer, &s, 2);
- len += 2;
-
- send(this->GetFD(), reinterpret_cast<char *>(buffer), len, 0);
- }
- catch (const SocketException &) { }
-
- delete packet;
- packet = NULL;
- }
-
- SocketEngine::Change(this, false, SF_WRITABLE);
- return true; /* Do not return false here, bind is unhappy we close the connection so soon after sending */
- }
- };
-
- TCPSocket(Manager *m, const Anope::string &ip, int port) : Socket(-1, ip.find(':') == Anope::string::npos ? AF_INET : AF_INET6), ListenSocket(ip, port, ip.find(':') != Anope::string::npos), manager(m) { }
-
- ClientSocket *OnAccept(int fd, const sockaddrs &addr) override
- {
- return new Client(this->manager, this, fd, addr);
- }
-};
-
-/* Listens for UDP requests */
-class UDPSocket final
- : public ReplySocket
-{
- Manager *manager;
- std::deque<Packet *> packets;
-
-public:
- UDPSocket(Manager *m, const Anope::string &ip, int port) : Socket(-1, ip.find(':') == Anope::string::npos ? AF_INET : AF_INET6, SOCK_DGRAM), manager(m) { }
-
- ~UDPSocket() override
- {
- for (const auto *packet : packets)
- delete packet;
- }
-
- void Reply(Packet *p) override
- {
- packets.push_back(p);
- SocketEngine::Change(this, true, SF_WRITABLE);
- }
-
- std::deque<Packet *>& GetPackets() { return packets; }
-
- bool ProcessRead() override
- {
- Log(LOG_DEBUG_2) << "Resolver: Reading from DNS UDP socket";
-
- unsigned char packet_buffer[524];
- sockaddrs from_server;
- socklen_t x = sizeof(from_server);
- int length = recvfrom(this->GetFD(), reinterpret_cast<char *>(&packet_buffer), sizeof(packet_buffer), 0, &from_server.sa, &x);
- return this->manager->HandlePacket(this, packet_buffer, length, &from_server);
- }
-
- bool ProcessWrite() override
- {
- Log(LOG_DEBUG_2) << "Resolver: Writing to DNS UDP socket";
-
- Packet *r = !packets.empty() ? packets.front() : NULL;
- if (r != NULL)
- {
- try
- {
- unsigned char buffer[524];
- unsigned short len = r->Pack(buffer, sizeof(buffer));
-
- sendto(this->GetFD(), reinterpret_cast<char *>(buffer), len, 0, &r->addr.sa, r->addr.size());
- }
- catch (const SocketException &) { }
-
- delete r;
- packets.pop_front();
- }
-
- if (packets.empty())
- SocketEngine::Change(this, false, SF_WRITABLE);
-
- return true;
- }
-};
-
-class NotifySocket final
- : public Socket
-{
- Packet *packet;
-public:
- NotifySocket(int family, Packet *p) : Socket(-1, family, SOCK_DGRAM), packet(p)
- {
- SocketEngine::Change(this, false, SF_READABLE);
- SocketEngine::Change(this, true, SF_WRITABLE);
- }
-
- bool ProcessWrite() override
- {
- if (!packet)
- return false;
-
- Log(LOG_DEBUG_2) << "Resolver: Notifying slave " << packet->addr.addr();
-
- try
- {
- unsigned char buffer[524];
- unsigned short len = packet->Pack(buffer, sizeof(buffer));
-
- sendto(this->GetFD(), reinterpret_cast<char *>(buffer), len, 0, &packet->addr.sa, packet->addr.size());
- }
- catch (const SocketException &) { }
-
- delete packet;
- packet = NULL;
-
- return false;
- }
-};
-
-class MyManager final
- : public Manager
- , public Timer
-{
- uint32_t serial;
-
- typedef std::unordered_map<Question, Query, Question::hash> cache_map;
- cache_map cache;
-
- TCPSocket *tcpsock = nullptr;
- UDPSocket *udpsock = nullptr;
-
- bool listen = false;
- sockaddrs addrs;
-
- std::vector<std::pair<Anope::string, short> > notify;
-public:
- std::map<unsigned short, Request *> requests;
-
- MyManager(Module *creator) : Manager(creator), Timer(300, Anope::CurTime, true), serial(Anope::CurTime), cur_id(rand())
- {
- }
-
- ~MyManager() override
- {
- delete udpsock;
- delete tcpsock;
-
- for (std::map<unsigned short, Request *>::iterator it = this->requests.begin(), it_end = this->requests.end(); it != it_end;)
- {
- Request *request = it->second;
- ++it;
-
- Query rr(*request);
- rr.error = ERROR_UNKNOWN;
- request->OnError(&rr);
-
- delete request;
- }
- this->requests.clear();
-
- this->cache.clear();
- }
-
- void SetIPPort(const Anope::string &nameserver, const Anope::string &ip, unsigned short port, std::vector<std::pair<Anope::string, short> > n)
- {
- delete udpsock;
- delete tcpsock;
-
- udpsock = NULL;
- tcpsock = NULL;
-
- try
- {
- this->addrs.pton(nameserver.find(':') != Anope::string::npos ? AF_INET6 : AF_INET, nameserver, 53);
-
- udpsock = new UDPSocket(this, ip, port);
-
- if (!ip.empty())
- {
- udpsock->Bind(ip, port);
- tcpsock = new TCPSocket(this, ip, port);
- listen = true;
- }
- }
- catch (const SocketException &ex)
- {
- Log() << "Unable to bind dns to " << ip << ":" << port << ": " << ex.GetReason();
- }
-
- notify = n;
- }
-
-private:
- unsigned short cur_id;
-
- unsigned short GetID()
- {
- if (this->udpsock->GetPackets().size() == 65535)
- throw SocketException("DNS queue full");
-
- do
- cur_id = (cur_id + 1) & 0xFFFF;
- while (!cur_id || this->requests.count(cur_id));
-
- return cur_id;
- }
-
-public:
- void Process(Request *req) override
- {
- Log(LOG_DEBUG_2) << "Resolver: Processing request to lookup " << req->name << ", of type " << req->type;
-
- if (req->use_cache && this->CheckCache(req))
- {
- Log(LOG_DEBUG_2) << "Resolver: Using cached result";
- delete req;
- return;
- }
-
- if (!this->udpsock)
- throw SocketException("No dns socket");
-
- req->id = GetID();
- this->requests[req->id] = req;
-
- req->SetSecs(timeout);
-
- auto *p = new Packet(this, &this->addrs);
- p->flags = QUERYFLAGS_RD;
- p->id = req->id;
- p->questions.push_back(*req);
-
- this->udpsock->Reply(p);
- }
-
- void RemoveRequest(Request *req) override
- {
- this->requests.erase(req->id);
- }
-
- bool HandlePacket(ReplySocket *s, const unsigned char *const packet_buffer, int length, sockaddrs *from) override
- {
- if (length < Packet::HEADER_LENGTH)
- return true;
-
- Packet recv_packet(this, from);
-
- try
- {
- recv_packet.Fill(packet_buffer, length);
- }
- catch (const SocketException &ex)
- {
- Log(LOG_DEBUG_2) << ex.GetReason();
- return true;
- }
-
- if (!(recv_packet.flags & QUERYFLAGS_QR))
- {
- if (!listen)
- return true;
- else if (recv_packet.questions.empty())
- {
- Log(LOG_DEBUG_2) << "Resolver: Received a question with no questions?";
- return true;
- }
-
- auto *packet = new Packet(recv_packet);
- packet->flags |= QUERYFLAGS_QR; /* This is a response */
- packet->flags |= QUERYFLAGS_AA; /* And we are authoritative */
-
- packet->answers.clear();
- packet->authorities.clear();
- packet->additional.clear();
-
- for (auto &q : recv_packet.questions)
- {
- if (q.type == QUERY_AXFR || q.type == QUERY_SOA)
- {
- ResourceRecord rr(q.name, QUERY_SOA);
- packet->answers.push_back(rr);
-
- if (q.type == QUERY_AXFR)
- {
- Anope::string token;
- spacesepstream sep(nameservers);
- while (sep.GetToken(token))
- {
- ResourceRecord rr2(q.name, QUERY_NS);
- rr2.rdata = token;
- packet->answers.push_back(rr2);
- }
- }
- break;
- }
- }
-
- FOREACH_MOD(OnDnsRequest, (recv_packet, packet));
-
- for (auto &q : recv_packet.questions)
- {
- if (q.type == QUERY_AXFR)
- {
- ResourceRecord rr(q.name, QUERY_SOA);
- packet->answers.push_back(rr);
- break;
- }
- }
-
- if (packet->answers.empty() && packet->authorities.empty() && packet->additional.empty() && packet->error == ERROR_NONE)
- packet->error = ERROR_REFUSED; // usually safe, won't cause an NXDOMAIN to get cached
-
- s->Reply(packet);
- return true;
- }
-
- if (from == NULL)
- {
- Log(LOG_DEBUG_2) << "Resolver: Received an answer over TCP. This is not supported.";
- return true;
- }
- else if (this->addrs != *from)
- {
- Log(LOG_DEBUG_2) << "Resolver: Received an answer from the wrong nameserver, Bad NAT or DNS forging attempt? '" << this->addrs.addr() << "' != '" << from->addr() << "'";
- return true;
- }
-
- std::map<unsigned short, Request *>::iterator it = this->requests.find(recv_packet.id);
- if (it == this->requests.end())
- {
- Log(LOG_DEBUG_2) << "Resolver: Received an answer for something we didn't request";
- return true;
- }
- Request *request = it->second;
-
- if (recv_packet.flags & QUERYFLAGS_OPCODE)
- {
- Log(LOG_DEBUG_2) << "Resolver: Received a nonstandard query";
- recv_packet.error = ERROR_NONSTANDARD_QUERY;
- request->OnError(&recv_packet);
- }
- else if (recv_packet.flags & QUERYFLAGS_RCODE)
- {
- Error error = ERROR_UNKNOWN;
-
- switch (recv_packet.flags & QUERYFLAGS_RCODE)
- {
- case 1:
- Log(LOG_DEBUG_2) << "Resolver: format error";
- error = ERROR_FORMAT_ERROR;
- break;
- case 2:
- Log(LOG_DEBUG_2) << "Resolver: server error";
- error = ERROR_SERVER_FAILURE;
- break;
- case 3:
- Log(LOG_DEBUG_2) << "Resolver: domain not found";
- error = ERROR_DOMAIN_NOT_FOUND;
- break;
- case 4:
- Log(LOG_DEBUG_2) << "Resolver: not implemented";
- error = ERROR_NOT_IMPLEMENTED;
- break;
- case 5:
- Log(LOG_DEBUG_2) << "Resolver: refused";
- error = ERROR_REFUSED;
- break;
- default:
- break;
- }
-
- recv_packet.error = error;
- request->OnError(&recv_packet);
- }
- else if (recv_packet.questions.empty() || recv_packet.answers.empty())
- {
- Log(LOG_DEBUG_2) << "Resolver: No resource records returned";
- recv_packet.error = ERROR_NO_RECORDS;
- request->OnError(&recv_packet);
- }
- else
- {
- Log(LOG_DEBUG_2) << "Resolver: Lookup complete for " << request->name;
- request->OnLookupComplete(&recv_packet);
- this->AddCache(recv_packet);
- }
-
- delete request;
- return true;
- }
-
- void UpdateSerial() override
- {
- serial = Anope::CurTime;
- }
-
- void Notify(const Anope::string &zone) override
- {
- /* notify slaves of the update */
- for (const auto &[ip, port] : notify)
- {
- sockaddrs addr;
- addr.pton(ip.find(':') != Anope::string::npos ? AF_INET6 : AF_INET, ip, port);
- if (!addr.valid())
- return;
-
- auto *packet = new Packet(this, &addr);
- packet->flags = QUERYFLAGS_AA | QUERYFLAGS_OPCODE_NOTIFY;
- try
- {
- packet->id = GetID();
- }
- catch (const SocketException &)
- {
- delete packet;
- continue;
- }
-
- packet->questions.emplace_back(zone, QUERY_SOA);
-
- new NotifySocket(ip.find(':') == Anope::string::npos ? AF_INET : AF_INET6, packet);
- }
- }
-
- uint32_t GetSerial() const override
- {
- return serial;
- }
-
- void Tick(time_t now) override
- {
- Log(LOG_DEBUG_2) << "Resolver: Purging DNS cache";
-
- for (cache_map::iterator it = this->cache.begin(), it_next; it != this->cache.end(); it = it_next)
- {
- const Query &q = it->second;
- const ResourceRecord &req = q.answers[0];
- it_next = it;
- ++it_next;
-
- if (req.created + static_cast<time_t>(req.ttl) < now)
- this->cache.erase(it);
- }
- }
-
-private:
- /** Add a record to the dns cache
- * @param r The record
- */
- void AddCache(Query &r)
- {
- const ResourceRecord &rr = r.answers[0];
- Log(LOG_DEBUG_3) << "Resolver cache: added cache for " << rr.name << " -> " << rr.rdata << ", ttl: " << rr.ttl;
- this->cache[r.questions[0]] = r;
- }
-
- /** Check the DNS cache to see if request can be handled by a cached result
- * @return true if a cached result was found.
- */
- bool CheckCache(Request *request)
- {
- cache_map::iterator it = this->cache.find(*request);
- if (it != this->cache.end())
- {
- Query &record = it->second;
- Log(LOG_DEBUG_3) << "Resolver: Using cached result for " << request->name;
- request->OnLookupComplete(&record);
- return true;
- }
-
- return false;
- }
-
-};
-
-class ModuleDNS final
- : public Module
-{
- MyManager manager;
-
- Anope::string nameserver;
- Anope::string ip;
- int port;
-
- std::vector<std::pair<Anope::string, short> > notify;
-
-public:
- ModuleDNS(const Anope::string &modname, const Anope::string &creator) : Module(modname, creator, EXTRA | VENDOR), manager(this)
- {
-
- }
-
- ~ModuleDNS() override
- {
- for (std::map<int, Socket *>::const_iterator it = SocketEngine::Sockets.begin(), it_end = SocketEngine::Sockets.end(); it != it_end;)
- {
- Socket *s = it->second;
- ++it;
-
- if (dynamic_cast<NotifySocket *>(s) || dynamic_cast<TCPSocket::Client *>(s))
- delete s;
- }
- }
-
- void OnReload(Configuration::Conf *conf) override
- {
- Configuration::Block *block = conf->GetModule(this);
-
- nameserver = block->Get<const Anope::string>("nameserver", "127.0.0.1");
- timeout = block->Get<time_t>("timeout", "5");
- ip = block->Get<const Anope::string>("ip", "0.0.0.0");
- port = block->Get<int>("port", "53");
- admin = block->Get<const Anope::string>("admin", "admin@example.com");
- nameservers = block->Get<const Anope::string>("nameservers", "ns1.example.com");
- refresh = block->Get<int>("refresh", "3600");
-
- for (int i = 0; i < block->CountBlock("notify"); ++i)
- {
- Configuration::Block *n = block->GetBlock("notify", i);
- Anope::string nip = n->Get<Anope::string>("ip");
- short nport = n->Get<short>("port");
-
- notify.emplace_back(nip, nport);
- }
-
- if (Anope::IsFile(nameserver))
- {
- std::ifstream f(nameserver.c_str());
- bool success = false;
-
- if (f.is_open())
- {
- for (Anope::string server; std::getline(f, server.str());)
- {
- if (server.find("nameserver") == 0)
- {
- size_t i = server.find_first_of("123456789");
- if (i != Anope::string::npos)
- {
- if (server.substr(i).is_pos_number_only())
- {
- nameserver = server.substr(i);
- Log(LOG_DEBUG) << "Nameserver set to " << nameserver;
- success = true;
- break;
- }
- }
- }
- }
-
- f.close();
- }
-
- if (!success)
- {
- Log() << "Unable to find nameserver, defaulting to 127.0.0.1";
- nameserver = "127.0.0.1";
- }
- }
-
- try
- {
- this->manager.SetIPPort(nameserver, ip, port, notify);
- }
- catch (const SocketException &ex)
- {
- throw ModuleException(ex.GetReason());
- }
- }
-
- void OnModuleUnload(User *u, Module *m) override
- {
- for (std::map<unsigned short, Request *>::iterator it = this->manager.requests.begin(), it_end = this->manager.requests.end(); it != it_end;)
- {
- unsigned short id = it->first;
- Request *req = it->second;
- ++it;
-
- if (req->creator == m)
- {
- Query rr(*req);
- rr.error = ERROR_UNLOADED;
- req->OnError(&rr);
-
- delete req;
- this->manager.requests.erase(id);
- }
- }
- }
-};
-
-MODULE_INIT(ModuleDNS)
generated by cgit (git 2.34.1) at 2025-06-17 15:10:19 +0000