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#include "Swiften/Network/DomainNameResolver.h"
#include "Swiften/Base/Platform.h"
#include <stdlib.h>
#include <boost/asio.hpp>
#include <idna.h>
#ifdef SWIFTEN_PLATFORM_WINDOWS
#undef UNICODE
#include <windows.h>
#include <windns.h>
#ifndef DNS_TYPE_SRV
#define DNS_TYPE_SRV 33
#endif
#else
#include <arpa/nameser.h>
#include <arpa/nameser_compat.h>
#include <resolv.h>
#endif
#include "Swiften/Network/DomainNameResolveException.h"
#include "Swiften/Base/String.h"
#include "Swiften/Base/ByteArray.h"
namespace Swift {
DomainNameResolver::DomainNameResolver() {
}
DomainNameResolver::~DomainNameResolver() {
}
HostAddressPort DomainNameResolver::resolve(const String& domain) {
char* output;
if (idna_to_ascii_8z(domain.getUTF8Data(), &output, 0) == IDNA_SUCCESS) {
std::string outputString(output);
free(output);
return resolveDomain(outputString);
}
else {
return resolveDomain(domain.getUTF8String());
}
}
HostAddressPort DomainNameResolver::resolveDomain(const std::string& domain) {
try {
return resolveXMPPService(domain);
}
catch (const DomainNameResolveException&) {
}
return HostAddressPort(resolveHostName(domain), 5222);
}
HostAddressPort DomainNameResolver::resolveXMPPService(const std::string& domain) {
std::string srvQuery = "_xmpp-client._tcp." + domain;
#if defined(SWIFTEN_PLATFORM_WINDOWS)
DNS_RECORD* responses;
// FIXME: This conversion doesn't work if unicode is deffed above
if (DnsQuery(srvQuery.c_str(), DNS_TYPE_SRV, DNS_QUERY_STANDARD, NULL, &responses, NULL) != ERROR_SUCCESS) {
throw DomainNameResolveException();
}
DNS_RECORD* currentEntry = responses;
while (currentEntry) {
if (currentEntry->wType == DNS_TYPE_SRV) {
int port = currentEntry->Data.SRV.wPort;
try {
// The pNameTarget is actually a PCWSTR, so I would have expected this
// conversion to not work at all, but it does.
// Actually, it doesn't. Fix this and remove explicit cast
// Remove unicode undef above as well
std::string hostname((const char*) currentEntry->Data.SRV.pNameTarget);
HostAddress address = resolveHostName(hostname);
DnsRecordListFree(responses, DnsFreeRecordList);
return HostAddressPort(address, port);
}
catch (const DomainNameResolveException&) {
}
}
currentEntry = currentEntry->pNext;
}
DnsRecordListFree(responses, DnsFreeRecordList);
#else
ByteArray response;
response.resize(NS_PACKETSZ);
int responseLength = res_query(const_cast<char*>(srvQuery.c_str()), ns_c_in, ns_t_srv, reinterpret_cast<u_char*>(response.getData()), response.getSize());
if (responseLength == -1) {
throw DomainNameResolveException();
}
// Parse header
HEADER* header = reinterpret_cast<HEADER*>(response.getData());
unsigned char* messageStart = reinterpret_cast<unsigned char*>(response.getData());
unsigned char* messageEnd = messageStart + responseLength;
unsigned char* currentEntry = messageStart + NS_HFIXEDSZ;
// Skip over the queries
int queriesCount = ntohs(header->qdcount);
while (queriesCount > 0) {
int entryLength = dn_skipname(currentEntry, messageEnd);
if (entryLength < 0) {
throw DomainNameResolveException();
}
currentEntry += entryLength + NS_QFIXEDSZ;
queriesCount--;
}
// Process the SRV answers
int answersCount = ntohs(header->ancount);
while (answersCount > 0) {
int entryLength = dn_skipname(currentEntry, messageEnd);
currentEntry += entryLength;
currentEntry += NS_RRFIXEDSZ;
// Uninteresting information
currentEntry += 2; // PRIORITY
currentEntry += 2; // WEIGHT
// Port
if (currentEntry >= messageEnd) {
throw DomainNameResolveException();
}
int port = ns_get16(currentEntry);
currentEntry += 2;
// Hostname
if (currentEntry >= messageEnd) {
throw DomainNameResolveException();
}
ByteArray entry;
entry.resize(NS_MAXDNAME);
entryLength = dn_expand(messageStart, messageEnd, currentEntry, entry.getData(), entry.getSize());
if (entryLength < 0) {
throw DomainNameResolveException();
}
try {
// Resolve the hostname
std::string hostname(entry.getData(), entryLength);
HostAddress address = resolveHostName(hostname);
return HostAddressPort(address, port);
}
catch (const DomainNameResolveException&) {
}
currentEntry += entryLength;
answersCount--;
}
#endif
throw DomainNameResolveException();
}
HostAddress DomainNameResolver::resolveHostName(const std::string& hostname) {
boost::asio::io_service ioService;
boost::asio::ip::tcp::resolver resolver(ioService);
boost::asio::ip::tcp::resolver::query query(hostname, "5222");
try {
boost::asio::ip::tcp::resolver::iterator endpointIterator = resolver.resolve(query);
if (endpointIterator == boost::asio::ip::tcp::resolver::iterator()) {
throw DomainNameResolveException();
}
boost::asio::ip::address address = (*endpointIterator).endpoint().address();
if (address.is_v4()) {
return HostAddress(&address.to_v4().to_bytes()[0], 4);
}
else {
return HostAddress(&address.to_v6().to_bytes()[0], 16);
}
}
catch (...) {
throw DomainNameResolveException();
}
}
}
|
Swift