Add mDNS device discovery for adb client
Test: Was able to discover a raspberry pi.
Bug: 28074466
(cherry picked from e292cd16760321fccc99c8c261cb92fa4b6462ab)
Change-Id: Id9571576457a4a0a078e48a274a4e8eac78bfe2b
diff --git a/adb/transport_mdns.cpp b/adb/transport_mdns.cpp
new file mode 100644
index 0000000..b63fc83
--- /dev/null
+++ b/adb/transport_mdns.cpp
@@ -0,0 +1,257 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define TRACE_TAG TRANSPORT
+
+#include "transport.h"
+
+#include <arpa/inet.h>
+
+#include <android-base/stringprintf.h>
+#include <dns_sd.h>
+
+#include "adb_mdns.h"
+#include "adb_trace.h"
+#include "fdevent.h"
+#include "sysdeps.h"
+
+static DNSServiceRef service_ref;
+static fdevent service_ref_fde;
+
+static void register_service_ip(DNSServiceRef sdRef,
+ DNSServiceFlags flags,
+ uint32_t interfaceIndex,
+ DNSServiceErrorType errorCode,
+ const char* hostname,
+ const sockaddr* address,
+ uint32_t ttl,
+ void* context);
+
+static void pump_service_ref(int /*fd*/, unsigned ev, void* data) {
+ DNSServiceRef* ref = reinterpret_cast<DNSServiceRef*>(data);
+
+ if (ev & FDE_READ)
+ DNSServiceProcessResult(*ref);
+}
+
+class AsyncServiceRef {
+ public:
+ bool Initialized() {
+ return initialized_;
+ }
+
+ virtual ~AsyncServiceRef() {
+ if (! initialized_) {
+ return;
+ }
+
+ DNSServiceRefDeallocate(sdRef_);
+ fdevent_remove(&fde_);
+ }
+
+ protected:
+ DNSServiceRef sdRef_;
+
+ void Initialize() {
+ fdevent_install(&fde_, DNSServiceRefSockFD(sdRef_),
+ pump_service_ref, &sdRef_);
+ fdevent_set(&fde_, FDE_READ);
+ initialized_ = true;
+ }
+
+ private:
+ bool initialized_;
+ fdevent fde_;
+};
+
+class ResolvedService : public AsyncServiceRef {
+ public:
+ virtual ~ResolvedService() = default;
+
+ ResolvedService(std::string name, uint32_t interfaceIndex,
+ const char* hosttarget, uint16_t port) :
+ name_(name),
+ port_(port) {
+ DNSServiceErrorType ret =
+ DNSServiceGetAddrInfo(
+ &sdRef_, 0, interfaceIndex,
+ kDNSServiceProtocol_IPv6|kDNSServiceProtocol_IPv4, hosttarget,
+ register_service_ip, reinterpret_cast<void*>(this));
+
+ if (ret != kDNSServiceErr_NoError) {
+ D("Got %d from DNSServiceGetAddrInfo.", ret);
+ } else {
+ Initialize();
+ }
+ }
+
+ void Connect(const sockaddr* address) {
+ char ip_addr[INET6_ADDRSTRLEN];
+ const void* ip_addr_data;
+ const char* addr_format;
+
+ if (address->sa_family == AF_INET) {
+ ip_addr_data =
+ &reinterpret_cast<const sockaddr_in*>(address)->sin_addr;
+ addr_format = "%s:%hu";
+ } else if (address->sa_family == AF_INET6) {
+ ip_addr_data =
+ &reinterpret_cast<const sockaddr_in6*>(address)->sin6_addr;
+ addr_format = "[%s]:%hu";
+ } else { // Should be impossible
+ D("mDNS resolved non-IP address.");
+ return;
+ }
+
+ if (!inet_ntop(address->sa_family, ip_addr_data, ip_addr,
+ INET6_ADDRSTRLEN)) {
+ D("Could not convert IP address to string.");
+ return;
+ }
+
+ std::string response;
+ connect_device(android::base::StringPrintf(addr_format, ip_addr, port_),
+ &response);
+ D("Connect to %s (%s:%hu) : %s", name_.c_str(), ip_addr, port_,
+ response.c_str());
+ }
+
+ private:
+ std::string name_;
+ const uint16_t port_;
+};
+
+static void register_service_ip(DNSServiceRef /*sdRef*/,
+ DNSServiceFlags /*flags*/,
+ uint32_t /*interfaceIndex*/,
+ DNSServiceErrorType /*errorCode*/,
+ const char* /*hostname*/,
+ const sockaddr* address,
+ uint32_t /*ttl*/,
+ void* context) {
+ std::unique_ptr<ResolvedService> data(
+ reinterpret_cast<ResolvedService*>(context));
+ data->Connect(address);
+}
+
+static void register_resolved_mdns_service(DNSServiceRef sdRef,
+ DNSServiceFlags flags,
+ uint32_t interfaceIndex,
+ DNSServiceErrorType errorCode,
+ const char* fullname,
+ const char* hosttarget,
+ uint16_t port,
+ uint16_t txtLen,
+ const unsigned char* txtRecord,
+ void* context);
+
+class DiscoveredService : public AsyncServiceRef {
+ public:
+ DiscoveredService(uint32_t interfaceIndex, const char* serviceName,
+ const char* regtype, const char* domain)
+ : serviceName_(serviceName) {
+
+ DNSServiceErrorType ret =
+ DNSServiceResolve(&sdRef_, 0, interfaceIndex, serviceName, regtype,
+ domain, register_resolved_mdns_service,
+ reinterpret_cast<void*>(this));
+
+ if (ret != kDNSServiceErr_NoError) {
+ D("Got %d from DNSServiceResolve.", ret);
+ } else {
+ Initialize();
+ }
+ }
+
+ const char* ServiceName() {
+ return serviceName_.c_str();
+ }
+
+ private:
+ std::string serviceName_;
+};
+
+static void register_resolved_mdns_service(DNSServiceRef sdRef,
+ DNSServiceFlags flags,
+ uint32_t interfaceIndex,
+ DNSServiceErrorType errorCode,
+ const char* fullname,
+ const char* hosttarget,
+ uint16_t port,
+ uint16_t /*txtLen*/,
+ const unsigned char* /*txtRecord*/,
+ void* context) {
+ std::unique_ptr<DiscoveredService> discovered(
+ reinterpret_cast<DiscoveredService*>(context));
+
+ if (errorCode != kDNSServiceErr_NoError) {
+ D("Got error %d resolving service.", errorCode);
+ return;
+ }
+
+
+ auto resolved =
+ new ResolvedService(discovered->ServiceName(),
+ interfaceIndex, hosttarget, ntohs(port));
+
+ if (! resolved->Initialized()) {
+ delete resolved;
+ }
+
+ if (flags) { /* Only ever equals MoreComing or 0 */
+ discovered.release();
+ }
+}
+
+static void register_mdns_transport(DNSServiceRef sdRef,
+ DNSServiceFlags flags,
+ uint32_t interfaceIndex,
+ DNSServiceErrorType errorCode,
+ const char* serviceName,
+ const char* regtype,
+ const char* domain,
+ void* /*context*/) {
+ if (errorCode != kDNSServiceErr_NoError) {
+ D("Got error %d during mDNS browse.", errorCode);
+ DNSServiceRefDeallocate(sdRef);
+ fdevent_remove(&service_ref_fde);
+ return;
+ }
+
+ auto discovered = new DiscoveredService(interfaceIndex, serviceName,
+ regtype, domain);
+
+ if (! discovered->Initialized()) {
+ delete discovered;
+ }
+}
+
+void init_mdns_transport_discovery(void) {
+ DNSServiceErrorType errorCode =
+ DNSServiceBrowse(&service_ref, 0, 0, kADBServiceType, nullptr,
+ register_mdns_transport, nullptr);
+
+ if (errorCode != kDNSServiceErr_NoError) {
+ D("Got %d initiating mDNS browse.", errorCode);
+ return;
+ }
+
+ fdevent_install(&service_ref_fde,
+ DNSServiceRefSockFD(service_ref),
+ pump_service_ref,
+ &service_ref);
+ fdevent_set(&service_ref_fde, FDE_READ);
+}