diff options
Diffstat (limited to 'Swiften/Network/DomainNameResolver.cpp')
-rw-r--r-- | Swiften/Network/DomainNameResolver.cpp | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/Swiften/Network/DomainNameResolver.cpp b/Swiften/Network/DomainNameResolver.cpp new file mode 100644 index 0000000..d2bbf0d --- /dev/null +++ b/Swiften/Network/DomainNameResolver.cpp @@ -0,0 +1,176 @@ +#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(); + } +} + +} |