#include <iostream>
#endif
-#define DEBUG_RESOLV
-
NameServer::Name::Name(const std::string& s)
{
std::istringstream iss(s);
return os << name.back();
}
-NameServer::Name::operator std::string ()
+NameServer::Name::operator std::string () const
{
std::stringstream ss;
ss << *this;
throw std::runtime_error("Error al parsear");
z.name = sname;
#ifdef DEBUG_PARSER
- std::cerr << "parsezone: IP = " << ip << "\n\n";
+ std::cout << "NameServer::parsezone: IP = " << ip << "\n\n";
#endif
z.parent = IPAddr(ip);
// un record por linea, sin líneas vacías
throw std::runtime_error("Error al parsear");
typedef NameServer::Record Rec;
#ifdef DEBUG_PARSER
- std::cerr << "parsezone: IP = " << ip << "\n\n";
+ std::cout << "NameServer::parsezone: IP = " << ip << "\n\n";
#endif
Rec r((type == "NS") ? Rec::NS : Rec::A, IPAddr(ip));
z.records.insert(NameServer::Zone::records_t::value_type(key, r));
}
#ifdef DEBUG_PARSER
- std::cerr << "parsezone: " << z << "\n\n";
+ std::cout << "NameServer::parsezone: " << z << "\n\n";
#endif
return is;
}
}
/// Constructor
-NameServer::NameServer(std::istream& is)
- throw (std::runtime_error)
+NameServer::NameServer(std::istream& is, IPIn& ipin, IPOut& ipout,
+ DevQue& req_que, DevQue& res_que, DevQue& snd_que)
+ throw (std::runtime_error):
+ ipin(ipin), ipout(ipout), req_que(req_que), res_que(res_que),
+ snd_que(snd_que)
{
Zone z;
while (parsezone(is, z))
zones.push_back(z);
z.clear();
#ifdef DEBUG_PARSER
- std::cerr << "NameServer: " << z << "\n\n";
+ std::cout << "NameServer::NameServer: " << z << "\n\n";
#endif
}
+
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::NameServer: req_que_id = " << req_que.que_id
+ << ", res_que_id = " << res_que.que_id
+ << ", snd_que_id = " << snd_que.que_id << "\n";
+#endif
}
/// Devuelve la parte izquierda de n, si la parte derecha coincide exactamente
r.push_back(n[i++]);
std::reverse(r.begin(), r.end());
#ifdef DEBUG_NAME
- std::cerr << "name_split(" << n << ", " << m << ") -> " << r << "\n";
+ std::cout << "NameServer::name_split(" << n << ", " << m << ") -> "
+ << r << "\n";
#endif
return r;
}
struct search_zone: std::unary_function< NameServer::Zone, bool >
{
bool local;
- NameServer::CacheRecord crecord;
+ ResolvProtoResponse resp;
const NameServer::Name& name;
search_zone(const NameServer::Name& n): local(false), name(n) {}
bool operator() (const NameServer::Zone& z)
if ((local_part.size() > 1) && r.type != NameServer::Record::NS)
continue;
found = true;
- crecord.ttl = z.ttl;
- crecord.records.push_back(r);
+ resp.ret = (r.type == NameServer::Record::NS) ? RP_RES_NS
+ : RP_RES_A;
+ resp.ttl = z.ttl;
+ resp.ips.push_back(r.ip);
}
}
return found;
}
};
-void NameServer::resolv_next(const Name& n)
+/// Resuelve un nombre de forma directa (no recursiva)
+ResolvProtoResponse NameServer::resolv_direct(const Name& n)
{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::resolv_direct()\n";
+#endif
#ifdef DEBUG_RESOLV
- std::cerr << "resolv_next -> tratando de resolver: " << n << "\n";
+ std::cout << "NameServer::resolv_direct -> tratando de resolver: "
+ << n << "\n";
#endif
search_zone zs(n);
bool found;
break;
if (found)
{
- // TODO mandar resultados?
#ifdef DEBUG_RESOLV
- std::cerr << "resolv_next found (local/hijo): " << zs.crecord << "\n";
+ std::cout << "NameServer::resolv_direct -> found (local/hijo): "
+ << zs.resp << "\n";
#endif
- return;
+ return zs.resp;
}
if (zs.local)
{
- // TODO mandar NOT FOUND
#ifdef DEBUG_RESOLV
- std::cerr << "resolv_next NOT FOUND (es local pero no existe)\n";
+ std::cout << "NameServer::resolv_direct -> NOT FOUND (es local pero "
+ "no existe)\n";
#endif
- return;
+ return ResolvProtoResponse(RP_RES_NOTFOUND);
}
- cache_t::const_iterator i = cache.find(n);
- // TODO TTL!?!
+ cache_t::iterator i = cache.find(n);
if (i != cache.end())
{
- // TODO mandar resultados?
+ const CacheRecord& cr = i->second;
#ifdef DEBUG_RESOLV
- std::cerr << "resolv_next found (en cache): " << i->second << "\n";
+ std::cout << "NameServer::resolv_direct -> found (en cache): "
+ << cr << "\n";
#endif
- return;
+ if (unsigned(time(NULL)) > cr.expire) // Expiró
+ {
+ cache.erase(i);
+#ifdef DEBUG_RESOLV
+ std::cout << " -> pero no sirve, expiró "
+ "hace unos " << (time(NULL) - cr.expire) << " segundos\n";
+#endif
+ }
+ else
+ {
+ return ResolvProtoResponse(RP_RES_A, cr.ttl, cr.ips);
+ }
}
- // TODO enviar nameserver padre, si no hay padre, mandar NOT FOUND
if (zones.size())
{
+ // Busco una zona con padre para ver si puedo "trepar"
+ for (zones_t::const_iterator i = zones.begin(); i != zones.end(); ++i)
+ {
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_direct -> evaluando padre "
+ << i->parent << "\n";
+#endif
+ if (i->parent != IPAddr(0))
+ {
#ifdef DEBUG_RESOLV
- std::cerr << "resolv_next found (al padre): " << zones.front().parent
- << "\n";
- return;
+ std::cout << "NameServer::resolv_direct -> found (al padre): "
+ << i->parent << "\n";
#endif
+ ResolvProtoResponse rpr(RP_RES_NS, i->ttl);
+ rpr.ips.push_back(i->parent);
+ return rpr;
+ }
+ }
+ }
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_direct -> NOT FOUND (no hay padre)\n";
+#endif
+ // No hay padre, no puedo hacer nada más
+ return ResolvProtoResponse(RP_RES_NOTFOUND);
+}
+
+/// Resuelve un nombre de forma recursiva
+ResolvProtoResponse NameServer::resolv_recursive(const Name& n)
+{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::resolv_recursive()\n";
+#endif
+ ResolvProtoResponse rpr = resolv_direct(n);
+ switch (rpr.ret)
+ {
+ case RP_RES_NS:
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_recursive -> redirect a "
+ << rpr << "\n";
+#endif
+ return resolv_recursive_r(n, rpr); // Sigo "bajando"
+ case RP_RES_A:
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_recursive -> gotcha! "
+ << rpr << "\n";
+#endif
+ break;
+ }
+ return rpr; // Devuelvo el A o NOTFOUND
+}
+
+/// Resuelve un nombre de forma recursiva entrando a otros ns
+ResolvProtoResponse NameServer::resolv_recursive_r(const Name& n,
+ ResolvProtoResponse rpr)
+{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::resolv_recursive_r()\n";
+#endif
+ ResolvProtoResponse r;
+ for (ResolvProtoResponse::ipvec_t::const_iterator ip = rpr.ips.begin();
+ ip != rpr.ips.end(); ++ip)
+ {
+ r = query(n, *ip);
+ switch (r.ret)
+ {
+ case RP_RES_NS:
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_recursive_r -> redirect a "
+ << r << "\n";
+#endif
+ return resolv_recursive_r(n, r); // Sigo "bajando"
+ case RP_RES_NOTFOUND:
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_recursive_r -> NOT FOUND en "
+ << *ip << ", sigo probando\n";
+#endif
+ break; // Sigo probando del mismo nivel
+ case RP_RES_A:
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::resolv_recursive_r -> gotcha! "
+ << r << "\n";
+#endif
+ return r; // Gotcha!
+ }
}
- // TODO enviar NOT FOUND
#ifdef DEBUG_RESOLV
- std::cerr << "resolv_next NOT FOUND (no hay padre)\n";
+ std::cout << "NameServer::resolv_recursive_r -> NOT FOUND, no hay más "
+ "por hacer\n";
#endif
+ return r; // NOTFOUND
+}
+
+/// Consulta a otro name server sobre un nombre
+ResolvProtoResponse NameServer::query(const Name& n, const IPAddr& ip)
+{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::query()\n";
+#endif
+ ResolvProtoRequest r(std::string(n), RP_REQ_DIRECT);
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::query -> pidiendo " << r << " a " << ip << "\n";
+#endif
+ // Envía a través de la cola de envío
+ snd_que.transmit(std::string(r), ip);
+ Dev::mac_type mac = ip;
+ std::string buf = res_que.receive(mac);
+ ResolvProtoResponse resp(buf);
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::query -> recibido " << resp << " de "
+ << ip << "\n";
+#endif
+ // Agrego a cache
+ if (resp.ret == RP_RES_A)
+ cache[n] = CacheRecord(time(NULL) + resp.ttl, resp.ttl, resp.ips);
+ return resp;
+}
+
+void NameServer::recv_loop()
+{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::recv_loop()\n";
+#endif
+ while (true)
+ {
+ IPAddr src, dst;
+ uint8_t proto;
+ std::string s = ipin.recv(proto, src, dst);
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::recv_loop() -> recibido len=" << s.size()
+ << " de " << src << " para " << dst << " (proto = "
+ << unsigned(proto) << ")\n";
+#endif
+ if (proto == RESOLV_PROTO) // Si es para nosotros
+ {
+ rp_pkt_type_t type;
+ memcpy(&type, s.data(), sizeof(uint8_t));
+ switch (type)
+ {
+ // Request
+ case RP_REQ_DIRECT:
+ case RP_REQ_RECURSIVE:
+#ifdef DEBUG_RESOLV
+ std::cout << "---> " << ResolvProtoRequest(s) << "\n";
+#endif
+ req_que.transmit(s, src); // Encolo
+ break;
+ // Response
+ default:
+#ifdef DEBUG_RESOLV
+ std::cout << "---> " << ResolvProtoResponse(s) << "\n";
+#endif
+ res_que.transmit(s, src); // Encolo
+ }
+ }
+ }
+}
+
+void NameServer::send_loop()
+{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::send_loop()\n";
+#endif
+ while (true)
+ {
+ Dev::mac_type mac = 0;
+ std::string buf = snd_que.receive(mac);
+#ifdef DEBUG_RESOLV
+ uint8_t type;
+ memcpy(&type, buf.data(), sizeof(uint8_t));
+ std::cout << "NameServer::send_loop() -> envío ";
+ if (type == RP_REQ_DIRECT || type == RP_REQ_RECURSIVE)
+ std::cout << "request " << ResolvProtoRequest(buf) << "\n";
+ else
+ std::cout << "response " << ResolvProtoResponse(buf) << "\n";
+#endif
+ ipout.send(buf, RESOLV_PROTO, IPAddr(mac));
+ }
+}
+
+void NameServer::req_loop()
+{
+#ifdef DEBUG_TRACE
+ std::cout << "NameServer::req_loop()\n";
+#endif
+ while (true)
+ {
+#ifdef DEBUG_RESOLV
+ std::cout << "----------------------------------------------------\n";
+#endif
+ Dev::mac_type mac = 0;
+ ResolvProtoRequest req(req_que.receive(mac));
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::req_loop() -> recibido " << req << "\n";
+#endif
+ ResolvProtoResponse res
+ = (req.query_type == RP_REQ_DIRECT)
+ ? resolv_direct(req.name)
+ : resolv_recursive(req.name);
+#ifdef DEBUG_RESOLV
+ std::cout << "NameServer::req_loop() -> respondo " << res << "\n";
+#endif
+ snd_que.transmit(std::string(res), IPAddr(mac));
+ }
}
std::ostream& operator<< (std::ostream& os, const NameServer::Record::type_t& t)
std::ostream& operator<< (std::ostream& os, const NameServer::CacheRecord& cr)
{
- os << "CacheRecord(ttl=" << cr.ttl << ", records=";
- std::copy(cr.records.begin(), cr.records.end(),
- std::ostream_iterator< NameServer::Record >(os, ","));
+ os << "CacheRecord(expire=" << cr.expire << " [now=" << time(NULL)
+ << "], ttl=" << cr.ttl << ", records=";
+ std::copy(cr.ips.begin(), cr.ips.end(),
+ std::ostream_iterator< IPAddr >(os, ","));
return os << ")";
}