Fixing logic for using android_setsocknetwork() with bind().

If android_setsocknetwork() is available, and it fails, then bind()
should *not* be called, and an error should be returned.

If it succeeds, then bind should be called, but with an "any" address.

This is to prevent cases where sockets are sent with a source address
that doesn't match the network interface they're sent on. See bug below.

This CL also changes "NetworkBinderResults" to an enum class, and
renames it to "NetworkBinderResult".

BUG=webrtc:7026

Review-Url: https://codereview.webrtc.org/2646863005
Cr-Commit-Position: refs/heads/master@{#16597}
This commit is contained in:
deadbeef
2017-02-13 15:41:59 -08:00
committed by Commit bot
parent 06b7e5ce1f
commit c874d1296a
6 changed files with 101 additions and 30 deletions

View File

@ -19,13 +19,12 @@ namespace rtc {
class IPAddress;
// Error values are negative.
enum NetworkBindingResults {
NETWORK_BIND_SUCCESS = 0, // No error
NETWORK_BIND_FAILURE = -1, // Generic error
NETWORK_BIND_NOT_IMPLEMENTED = -2,
NETWORK_BIND_ADDRESS_NOT_FOUND = -3,
NETWORK_BIND_NETWORK_CHANGED = -4
enum class NetworkBindingResult {
SUCCESS = 0, // No error
FAILURE = -1, // Generic error
NOT_IMPLEMENTED = -2,
ADDRESS_NOT_FOUND = -3,
NETWORK_CHANGED = -4
};
enum AdapterType {
@ -44,7 +43,9 @@ class NetworkBinderInterface {
// packets on the socket |socket_fd| will be sent via that network.
// This is needed because some operating systems (like Android) require a
// special bind call to put packets on a non-default network interface.
virtual int BindSocketToNetwork(int socket_fd, const IPAddress& address) = 0;
virtual NetworkBindingResult BindSocketToNetwork(
int socket_fd,
const IPAddress& address) = 0;
virtual ~NetworkBinderInterface() {}
};

View File

@ -190,8 +190,42 @@ SocketAddress PhysicalSocket::GetRemoteAddress() const {
}
int PhysicalSocket::Bind(const SocketAddress& bind_addr) {
SocketAddress copied_bind_addr = bind_addr;
// If a network binder is available, use it to bind a socket to an interface
// instead of bind(), since this is more reliable on an OS with a weak host
// model.
if (ss_->network_binder()) {
NetworkBindingResult result =
ss_->network_binder()->BindSocketToNetwork(s_, bind_addr.ipaddr());
if (result == NetworkBindingResult::SUCCESS) {
// Since the network binder handled binding the socket to the desired
// network interface, we don't need to (and shouldn't) include an IP in
// the bind() call; bind() just needs to assign a port.
copied_bind_addr.SetIP(GetAnyIP(copied_bind_addr.ipaddr().family()));
} else if (result == NetworkBindingResult::NOT_IMPLEMENTED) {
LOG(LS_INFO) << "Can't bind socket to network because "
"network binding is not implemented for this OS.";
} else {
if (bind_addr.IsLoopbackIP()) {
// If we couldn't bind to a loopback IP (which should only happen in
// test scenarios), continue on. This may be expected behavior.
LOG(LS_VERBOSE) << "Binding socket to loopback address "
<< bind_addr.ipaddr().ToString()
<< " failed; result: " << static_cast<int>(result);
} else {
LOG(LS_WARNING) << "Binding socket to network address "
<< bind_addr.ipaddr().ToString()
<< " failed; result: " << static_cast<int>(result);
// If a network binding was attempted and failed, we should stop here
// and not try to use the socket. Otherwise, we may end up sending
// packets with an invalid source address.
// See: https://bugs.chromium.org/p/webrtc/issues/detail?id=7026
return -1;
}
}
}
sockaddr_storage addr_storage;
size_t len = bind_addr.ToSockAddrStorage(&addr_storage);
size_t len = copied_bind_addr.ToSockAddrStorage(&addr_storage);
sockaddr* addr = reinterpret_cast<sockaddr*>(&addr_storage);
int err = ::bind(s_, addr, static_cast<int>(len));
UpdateLastError();
@ -201,14 +235,6 @@ int PhysicalSocket::Bind(const SocketAddress& bind_addr) {
dbg_addr_.append(GetLocalAddress().ToString());
}
#endif
if (ss_->network_binder()) {
int result =
ss_->network_binder()->BindSocketToNetwork(s_, bind_addr.ipaddr());
if (result < 0) {
LOG(LS_INFO) << "Binding socket to network address "
<< bind_addr.ipaddr().ToString() << " result " << result;
}
}
return err;
}

View File

@ -14,6 +14,7 @@
#include "webrtc/base/gunit.h"
#include "webrtc/base/logging.h"
#include "webrtc/base/networkmonitor.h"
#include "webrtc/base/physicalsocketserver.h"
#include "webrtc/base/socket_unittest.h"
#include "webrtc/base/testutils.h"
@ -85,6 +86,18 @@ class FakePhysicalSocketServer : public PhysicalSocketServer {
PhysicalSocketTest* test_;
};
class FakeNetworkBinder : public NetworkBinderInterface {
public:
NetworkBindingResult BindSocketToNetwork(int, const IPAddress&) override {
return result_;
}
void set_result(NetworkBindingResult result) { result_ = result; }
private:
NetworkBindingResult result_ = NetworkBindingResult::SUCCESS;
};
class PhysicalSocketTest : public SocketTest {
public:
// Set flag to simluate failures when calling "::accept" on a AsyncSocket.
@ -415,6 +428,32 @@ TEST_F(PhysicalSocketTest, TestSocketRecvTimestampIPv6) {
}
#endif
// Verify that if the socket was unable to be bound to a real network interface
// (not loopback), Bind will return an error.
TEST_F(PhysicalSocketTest,
BindFailsIfNetworkBinderFailsForNonLoopbackInterface) {
FakeNetworkBinder fake_network_binder;
server_->set_network_binder(&fake_network_binder);
std::unique_ptr<AsyncSocket> socket(
server_->CreateAsyncSocket(AF_INET, SOCK_DGRAM));
fake_network_binder.set_result(NetworkBindingResult::FAILURE);
EXPECT_EQ(-1, socket->Bind(SocketAddress("192.168.0.1", 0)));
server_->set_network_binder(nullptr);
}
// For a loopback interface, failures to bind to the interface should be
// tolerated.
TEST_F(PhysicalSocketTest,
BindSucceedsIfNetworkBinderFailsForLoopbackInterface) {
FakeNetworkBinder fake_network_binder;
server_->set_network_binder(&fake_network_binder);
std::unique_ptr<AsyncSocket> socket(
server_->CreateAsyncSocket(AF_INET, SOCK_DGRAM));
fake_network_binder.set_result(NetworkBindingResult::FAILURE);
EXPECT_EQ(0, socket->Bind(SocketAddress(kIPv4Loopback, 0)));
server_->set_network_binder(nullptr);
}
class PosixSignalDeliveryTest : public testing::Test {
public:
static void RecordSignal(int signum) {

View File

@ -17,6 +17,9 @@
namespace rtc {
class MessageQueue;
// Needs to be forward declared because there's a circular dependency between
// NetworkMonitor and Thread.
// TODO(deadbeef): Fix this.
class NetworkBinderInterface;
// Provides the ability to wait for activity on a set of sockets. The Thread

View File

@ -236,8 +236,9 @@ void AndroidNetworkMonitor::Stop() {
// The implementation is largely taken from UDPSocketPosix::BindToNetwork in
// https://cs.chromium.org/chromium/src/net/udp/udp_socket_posix.cc
int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
const rtc::IPAddress& address) {
rtc::NetworkBindingResult AndroidNetworkMonitor::BindSocketToNetwork(
int socket_fd,
const rtc::IPAddress& address) {
RTC_CHECK(thread_checker_.CalledOnValidThread());
// Android prior to Lollipop didn't have support for binding sockets to
// networks. In that case it should not have reached here because
@ -246,12 +247,12 @@ int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
if (android_sdk_int_ < SDK_VERSION_LOLLIPOP) {
LOG(LS_ERROR) << "BindSocketToNetwork is not supported in Android SDK "
<< android_sdk_int_;
return rtc::NETWORK_BIND_NOT_IMPLEMENTED;
return rtc::NetworkBindingResult::NOT_IMPLEMENTED;
}
auto iter = network_handle_by_address_.find(address);
if (iter == network_handle_by_address_.end()) {
return rtc::NETWORK_BIND_ADDRESS_NOT_FOUND;
return rtc::NetworkBindingResult::ADDRESS_NOT_FOUND;
}
NetworkHandle network_handle = iter->second;
@ -271,7 +272,7 @@ int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
void* lib = dlopen(android_native_lib_path.c_str(), RTLD_NOW);
if (lib == nullptr) {
LOG(LS_ERROR) << "Library " << android_native_lib_path << " not found!";
return rtc::NETWORK_BIND_NOT_IMPLEMENTED;
return rtc::NetworkBindingResult::NOT_IMPLEMENTED;
}
marshmallowSetNetworkForSocket =
reinterpret_cast<MarshmallowSetNetworkForSocket>(
@ -279,7 +280,7 @@ int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
}
if (!marshmallowSetNetworkForSocket) {
LOG(LS_ERROR) << "Symbol marshmallowSetNetworkForSocket is not found";
return rtc::NETWORK_BIND_NOT_IMPLEMENTED;
return rtc::NetworkBindingResult::NOT_IMPLEMENTED;
}
rv = marshmallowSetNetworkForSocket(network_handle, socket_fd);
} else {
@ -300,7 +301,7 @@ int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
void* lib = dlopen(net_library_path.c_str(), RTLD_NOW | RTLD_NOLOAD);
if (lib == nullptr) {
LOG(LS_ERROR) << "Library " << net_library_path << " not found!";
return rtc::NETWORK_BIND_NOT_IMPLEMENTED;
return rtc::NetworkBindingResult::NOT_IMPLEMENTED;
}
lollipopSetNetworkForSocket =
reinterpret_cast<LollipopSetNetworkForSocket>(
@ -308,7 +309,7 @@ int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
}
if (!lollipopSetNetworkForSocket) {
LOG(LS_ERROR) << "Symbol lollipopSetNetworkForSocket is not found ";
return rtc::NETWORK_BIND_NOT_IMPLEMENTED;
return rtc::NetworkBindingResult::NOT_IMPLEMENTED;
}
rv = lollipopSetNetworkForSocket(network_handle, socket_fd);
}
@ -317,12 +318,12 @@ int AndroidNetworkMonitor::BindSocketToNetwork(int socket_fd,
// ERR_NETWORK_CHANGED, rather than MapSystemError(ENONET) which gives back
// the less descriptive ERR_FAILED.
if (rv == 0) {
return rtc::NETWORK_BIND_SUCCESS;
return rtc::NetworkBindingResult::SUCCESS;
}
if (rv == ENONET) {
return rtc::NETWORK_BIND_NETWORK_CHANGED;
return rtc::NetworkBindingResult::NETWORK_CHANGED;
}
return rtc::NETWORK_BIND_FAILURE;
return rtc::NetworkBindingResult::FAILURE;
}
void AndroidNetworkMonitor::OnNetworkConnected(

View File

@ -58,8 +58,9 @@ class AndroidNetworkMonitor : public rtc::NetworkMonitorBase,
void Start() override;
void Stop() override;
int BindSocketToNetwork(int socket_fd,
const rtc::IPAddress& address) override;
rtc::NetworkBindingResult BindSocketToNetwork(
int socket_fd,
const rtc::IPAddress& address) override;
rtc::AdapterType GetAdapterType(const std::string& if_name) override;
void OnNetworkConnected(const NetworkInformation& network_info);
void OnNetworkDisconnected(NetworkHandle network_handle);