diff options
Diffstat (limited to 'Swiften/Network/UnboundDomainNameResolver.cpp')
-rwxr-xr-x | Swiften/Network/UnboundDomainNameResolver.cpp | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/Swiften/Network/UnboundDomainNameResolver.cpp b/Swiften/Network/UnboundDomainNameResolver.cpp new file mode 100755 index 0000000..d986385 --- /dev/null +++ b/Swiften/Network/UnboundDomainNameResolver.cpp @@ -0,0 +1,241 @@ +/* + * Copyright (c) 2013 Tobias Markmann + * Licensed under the simplified BSD license. + * See Documentation/Licenses/BSD-simplified.txt for more information. + */ + +#include "UnboundDomainNameResolver.h" + +#include <vector> + +#include <boost/bind.hpp> +#include <boost/smart_ptr/make_shared.hpp> +#include <boost/enable_shared_from_this.hpp> + +#include <Swiften/Base/Log.h> +#include <Swiften/EventLoop/EventLoop.h> +#include <Swiften/Network/DomainNameAddressQuery.h> +#include <Swiften/Network/DomainNameResolveError.h> +#include <Swiften/Network/DomainNameServiceQuery.h> +#include <Swiften/Network/HostAddress.h> +#include <Swiften/Network/TimerFactory.h> + +#include <arpa/inet.h> +#include <unbound.h> +#include <ldns/ldns.h> +#include <unistd.h> + +namespace Swift { + +class UnboundQuery { + public: + UnboundQuery(UnboundDomainNameResolver* resolver, ub_ctx* context) : resolver(resolver), ubContext(context) {} + virtual ~UnboundQuery() {} + virtual void handleResult(int err, ub_result* result) = 0; + protected: + UnboundDomainNameResolver* resolver; + ub_ctx* ubContext; +}; + +struct UnboundWrapperHelper { + UnboundWrapperHelper(UnboundDomainNameResolver* resolver, boost::shared_ptr<UnboundQuery> query) : resolver(resolver), query(query) {} + UnboundDomainNameResolver* resolver; + boost::shared_ptr<UnboundQuery> query; +}; + +class UnboundDomainNameServiceQuery : public DomainNameServiceQuery, public UnboundQuery, public boost::enable_shared_from_this<UnboundDomainNameServiceQuery> { + public: + UnboundDomainNameServiceQuery(UnboundDomainNameResolver* resolver, ub_ctx* context, std::string name) : UnboundQuery(resolver, context), name(name) { + } + + virtual ~UnboundDomainNameServiceQuery() { } + + virtual void run() { + int retval; + UnboundWrapperHelper* helper = new UnboundWrapperHelper(resolver, shared_from_this()); + + retval = ub_resolve_async(ubContext, const_cast<char*>(name.c_str()), LDNS_RR_TYPE_SRV, + 1 /* CLASS IN (internet) */, + helper, UnboundDomainNameResolver::unbound_callback_wrapper, NULL); + if(retval != 0) { + SWIFT_LOG(debug) << "resolve error: " << ub_strerror(retval) << std::endl; + delete helper; + } + } + + void handleResult(int err, struct ub_result* result) { + std::vector<DomainNameServiceQuery::Result> serviceRecords; + + if(err != 0) { + SWIFT_LOG(debug) << "resolve error: " << ub_strerror(err) << std::endl; + } else { + if(result->havedata) { + ldns_pkt* replyPacket = 0; + ldns_buffer* buffer = ldns_buffer_new(1024); + if (buffer && ldns_wire2pkt(&replyPacket, static_cast<const uint8_t*>(result->answer_packet), result->answer_len) == LDNS_STATUS_OK) { + ldns_rr_list* rrList = ldns_pkt_answer(replyPacket); + for (size_t n = 0; n < ldns_rr_list_rr_count(rrList); n++) { + ldns_rr* rr = ldns_rr_list_rr(rrList, n); + if ((ldns_rr_get_type(rr) != LDNS_RR_TYPE_SRV) || + (ldns_rr_get_class(rr) != LDNS_RR_CLASS_IN) || + (ldns_rr_rd_count(rr) != 4)) { + continue; + } + + DomainNameServiceQuery::Result serviceRecord; + serviceRecord.priority = ldns_rdf2native_int16(ldns_rr_rdf(rr, 0)); + serviceRecord.weight = ldns_rdf2native_int16(ldns_rr_rdf(rr, 1)); + serviceRecord.port = ldns_rdf2native_int16(ldns_rr_rdf(rr, 2)); + + ldns_buffer_rewind(buffer); + if ((ldns_rdf2buffer_str_dname(buffer, ldns_rr_rdf(rr, 3)) != LDNS_STATUS_OK) || + (ldns_buffer_position(buffer) < 2) || + !ldns_buffer_reserve(buffer, 1)) { + // either name invalid, empty or buffer to small + continue; + } + char terminator = 0; + ldns_buffer_write(buffer, &terminator, sizeof(terminator)); + + serviceRecord.hostname = std::string(reinterpret_cast<char*>(ldns_buffer_at(buffer, 0))); + serviceRecords.push_back(serviceRecord); + SWIFT_LOG(debug) << "hostname " << serviceRecord.hostname << " added" << std::endl; + } + } + if (replyPacket) ldns_pkt_free(replyPacket); + if (buffer) ldns_buffer_free(buffer); + } + } + + ub_resolve_free(result); + onResult(serviceRecords); + } + + private: + std::string name; +}; + +class UnboundDomainNameAddressQuery : public DomainNameAddressQuery, public UnboundQuery, public boost::enable_shared_from_this<UnboundDomainNameAddressQuery> { + public: + UnboundDomainNameAddressQuery(UnboundDomainNameResolver* resolver, ub_ctx* context, std::string name) : UnboundQuery(resolver, context), name(name) { + } + + virtual ~UnboundDomainNameAddressQuery() { } + + virtual void run() { + int retval; + UnboundWrapperHelper* helper = new UnboundWrapperHelper(resolver, shared_from_this()); + + //FIXME: support AAAA queries in some way + retval = ub_resolve_async(ubContext, const_cast<char*>(name.c_str()), LDNS_RR_TYPE_A, + 1 /* CLASS IN (internet) */, + helper, UnboundDomainNameResolver::unbound_callback_wrapper, NULL); + if(retval != 0) { + SWIFT_LOG(debug) << "resolve error: " << ub_strerror(retval) << std::endl; + delete helper; + } + } + + void handleResult(int err, struct ub_result* result) { + std::vector<HostAddress> addresses; + boost::optional<DomainNameResolveError> error; + SWIFT_LOG(debug) << "Result for: " << name << std::endl; + + if(err != 0) { + SWIFT_LOG(debug) << "resolve error: " << ub_strerror(err) << std::endl; + error = DomainNameResolveError(); + } else { + if(result->havedata) { + for(int i=0; result->data[i]; i++) { + char address[100]; + const char* addressStr = 0; + if ((addressStr = inet_ntop(AF_INET, result->data[i], address, 100))) { + SWIFT_LOG(debug) << "IPv4 address: " << addressStr << std::endl; + addresses.push_back(HostAddress(std::string(addressStr))); + } else if ((addressStr = inet_ntop(AF_INET6, result->data[i], address, 100))) { + SWIFT_LOG(debug) << "IPv6 address: " << addressStr << std::endl; + addresses.push_back(HostAddress(std::string(addressStr))); + } else { + SWIFT_LOG(debug) << "inet_ntop() failed" << std::endl; + error = DomainNameResolveError(); + } + } + } else { + error = DomainNameResolveError(); + } + } + + ub_resolve_free(result); + onResult(addresses, error); + } + + private: + std::string name; +}; + +UnboundDomainNameResolver::UnboundDomainNameResolver(boost::shared_ptr<boost::asio::io_service> ioService, EventLoop* eventLoop) : ioService(ioService), ubDescriptior(*ioService), eventLoop(eventLoop) { + ubContext = ub_ctx_create(); + if(!ubContext) { + SWIFT_LOG(debug) << "could not create unbound context" << std::endl; + } + eventOwner = boost::make_shared<EventOwner>(); + + ub_ctx_async(ubContext, true); + + int ret; + + /* read /etc/resolv.conf for DNS proxy settings (from DHCP) */ + if( (ret=ub_ctx_resolvconf(ubContext, const_cast<char*>("/etc/resolv.conf"))) != 0) { + SWIFT_LOG(debug) << "error reading resolv.conf: " << ub_strerror(ret) << ". errno says: " << strerror(errno) << std::endl; + } + /* read /etc/hosts for locally supplied host addresses */ + if( (ret=ub_ctx_hosts(ubContext, const_cast<char*>("/etc/hosts"))) != 0) { + SWIFT_LOG(debug) << "error reading hosts: " << ub_strerror(ret) << ". errno says: " << strerror(errno) << std::endl; + } + + ubDescriptior.assign(ub_fd(ubContext)); + + ubDescriptior.async_read_some(boost::asio::null_buffers(), boost::bind(&UnboundDomainNameResolver::handleUBSocketReadable, this, boost::asio::placeholders::error)); +} + +UnboundDomainNameResolver::~UnboundDomainNameResolver() { + eventLoop->removeEventsFromOwner(eventOwner); + if (ubContext) { + ub_ctx_delete(ubContext); + } +} + +void UnboundDomainNameResolver::unbound_callback(boost::shared_ptr<UnboundQuery> query, int err, ub_result* result) { + query->handleResult(err, result); +} + +void UnboundDomainNameResolver::unbound_callback_wrapper(void* data, int err, ub_result* result) { + UnboundWrapperHelper* helper = static_cast<UnboundWrapperHelper*>(data); + UnboundDomainNameResolver* resolver = helper->resolver; + resolver->unbound_callback(helper->query, err, result); + delete helper; +} + +void UnboundDomainNameResolver::handleUBSocketReadable(boost::system::error_code) { + eventLoop->postEvent(boost::bind(&UnboundDomainNameResolver::processData, this), eventOwner); + ubDescriptior.async_read_some(boost::asio::null_buffers(), boost::bind(&UnboundDomainNameResolver::handleUBSocketReadable, this, boost::asio::placeholders::error)); +} + +void UnboundDomainNameResolver::processData() { + if (ub_poll(ubContext)) { + int ret = ub_process(ubContext); + if(ret != 0) { + SWIFT_LOG(debug) << "resolve error: " << ub_strerror(ret) << std::endl; + } + } +} + +boost::shared_ptr<DomainNameServiceQuery> UnboundDomainNameResolver::createServiceQuery(const std::string& name) { + return boost::make_shared<UnboundDomainNameServiceQuery>(this, ubContext, name); +} + +boost::shared_ptr<DomainNameAddressQuery> UnboundDomainNameResolver::createAddressQuery(const std::string& name) { + return boost::make_shared<UnboundDomainNameAddressQuery>(this, ubContext, name); +} + +} |