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/*
* Copyright 2014 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "rtc_base/ssl_adapter.h"
#include <memory>
#include <string>
#include <utility>
#include "absl/memory/memory.h"
#include "absl/strings/string_view.h"
#include "rtc_base/gunit.h"
#include "rtc_base/ip_address.h"
#include "rtc_base/message_digest.h"
#include "rtc_base/socket_stream.h"
#include "rtc_base/ssl_identity.h"
#include "rtc_base/ssl_stream_adapter.h"
#include "rtc_base/stream.h"
#include "rtc_base/string_encode.h"
#include "rtc_base/virtual_socket_server.h"
#include "test/gmock.h"
using ::testing::_;
using ::testing::Return;
static const int kTimeout = 5000;
static rtc::Socket* CreateSocket(const rtc::SSLMode& ssl_mode) {
rtc::SocketAddress address(rtc::IPAddress(INADDR_ANY), 0);
rtc::Socket* socket = rtc::Thread::Current()->socketserver()->CreateSocket(
address.family(),
(ssl_mode == rtc::SSL_MODE_DTLS) ? SOCK_DGRAM : SOCK_STREAM);
socket->Bind(address);
return socket;
}
static std::string GetSSLProtocolName(const rtc::SSLMode& ssl_mode) {
return (ssl_mode == rtc::SSL_MODE_DTLS) ? "DTLS" : "TLS";
}
// Simple mock for the certificate verifier.
class MockCertVerifier : public rtc::SSLCertificateVerifier {
public:
virtual ~MockCertVerifier() = default;
MOCK_METHOD(bool, Verify, (const rtc::SSLCertificate&), (override));
};
// TODO(benwright) - Move to using INSTANTIATE_TEST_SUITE_P instead of using
// duplicate test cases for simple parameter changes.
class SSLAdapterTestDummyClient : public sigslot::has_slots<> {
public:
explicit SSLAdapterTestDummyClient(const rtc::SSLMode& ssl_mode)
: ssl_mode_(ssl_mode) {
rtc::Socket* socket = CreateSocket(ssl_mode_);
ssl_adapter_.reset(rtc::SSLAdapter::Create(socket));
ssl_adapter_->SetMode(ssl_mode_);
// Ignore any certificate errors for the purpose of testing.
// Note: We do this only because we don't have a real certificate.
// NEVER USE THIS IN PRODUCTION CODE!
ssl_adapter_->SetIgnoreBadCert(true);
ssl_adapter_->SignalReadEvent.connect(
this, &SSLAdapterTestDummyClient::OnSSLAdapterReadEvent);
ssl_adapter_->SignalCloseEvent.connect(
this, &SSLAdapterTestDummyClient::OnSSLAdapterCloseEvent);
}
void SetIgnoreBadCert(bool ignore_bad_cert) {
ssl_adapter_->SetIgnoreBadCert(ignore_bad_cert);
}
void SetCertVerifier(rtc::SSLCertificateVerifier* ssl_cert_verifier) {
ssl_adapter_->SetCertVerifier(ssl_cert_verifier);
}
void SetAlpnProtocols(const std::vector<std::string>& protos) {
ssl_adapter_->SetAlpnProtocols(protos);
}
void SetEllipticCurves(const std::vector<std::string>& curves) {
ssl_adapter_->SetEllipticCurves(curves);
}
rtc::SocketAddress GetAddress() const {
return ssl_adapter_->GetLocalAddress();
}
rtc::Socket::ConnState GetState() const { return ssl_adapter_->GetState(); }
const std::string& GetReceivedData() const { return data_; }
int Connect(absl::string_view hostname, const rtc::SocketAddress& address) {
RTC_LOG(LS_INFO) << "Initiating connection with " << address.ToString();
int rv = ssl_adapter_->Connect(address);
if (rv == 0) {
RTC_LOG(LS_INFO) << "Starting " << GetSSLProtocolName(ssl_mode_)
<< " handshake with " << hostname;
if (ssl_adapter_->StartSSL(hostname) != 0) {
return -1;
}
}
return rv;
}
int Close() { return ssl_adapter_->Close(); }
int Send(absl::string_view message) {
RTC_LOG(LS_INFO) << "Client sending '" << message << "'";
return ssl_adapter_->Send(message.data(), message.length());
}
void OnSSLAdapterReadEvent(rtc::Socket* socket) {
char buffer[4096] = "";
// Read data received from the server and store it in our internal buffer.
int read = socket->Recv(buffer, sizeof(buffer) - 1, nullptr);
if (read != -1) {
buffer[read] = '\0';
RTC_LOG(LS_INFO) << "Client received '" << buffer << "'";
data_ += buffer;
}
}
void OnSSLAdapterCloseEvent(rtc::Socket* socket, int error) {
// OpenSSLAdapter signals handshake failure with a close event, but without
// closing the socket! Let's close the socket here. This way GetState() can
// return CS_CLOSED after failure.
if (socket->GetState() != rtc::Socket::CS_CLOSED) {
socket->Close();
}
}
private:
const rtc::SSLMode ssl_mode_;
std::unique_ptr<rtc::SSLAdapter> ssl_adapter_;
std::string data_;
};
class SSLAdapterTestDummyServer : public sigslot::has_slots<> {
public:
explicit SSLAdapterTestDummyServer(const rtc::SSLMode& ssl_mode,
const rtc::KeyParams& key_params)
: ssl_mode_(ssl_mode) {
// Generate a key pair and a certificate for this host.
ssl_identity_ = rtc::SSLIdentity::Create(GetHostname(), key_params);
server_socket_.reset(CreateSocket(ssl_mode_));
if (ssl_mode_ == rtc::SSL_MODE_TLS) {
server_socket_->SignalReadEvent.connect(
this, &SSLAdapterTestDummyServer::OnServerSocketReadEvent);
server_socket_->Listen(1);
}
RTC_LOG(LS_INFO) << ((ssl_mode_ == rtc::SSL_MODE_DTLS) ? "UDP" : "TCP")
<< " server listening on "
<< server_socket_->GetLocalAddress().ToString();
}
rtc::SocketAddress GetAddress() const {
return server_socket_->GetLocalAddress();
}
std::string GetHostname() const {
// Since we don't have a real certificate anyway, the value here doesn't
// really matter.
return "example.com";
}
const std::string& GetReceivedData() const { return data_; }
int Send(absl::string_view message) {
if (ssl_stream_adapter_ == nullptr ||
ssl_stream_adapter_->GetState() != rtc::SS_OPEN) {
// No connection yet.
return -1;
}
RTC_LOG(LS_INFO) << "Server sending '" << message << "'";
size_t written;
int error;
rtc::StreamResult r = ssl_stream_adapter_->Write(
rtc::MakeArrayView(reinterpret_cast<const uint8_t*>(message.data()),
message.size()),
written, error);
if (r == rtc::SR_SUCCESS) {
return written;
} else {
return -1;
}
}
void AcceptConnection(const rtc::SocketAddress& address) {
// Only a single connection is supported.
ASSERT_TRUE(ssl_stream_adapter_ == nullptr);
// This is only for DTLS.
ASSERT_EQ(rtc::SSL_MODE_DTLS, ssl_mode_);
// Transfer ownership of the socket to the SSLStreamAdapter object.
rtc::Socket* socket = server_socket_.release();
socket->Connect(address);
DoHandshake(socket);
}
void OnServerSocketReadEvent(rtc::Socket* socket) {
// Only a single connection is supported.
ASSERT_TRUE(ssl_stream_adapter_ == nullptr);
DoHandshake(server_socket_->Accept(nullptr));
}
void OnSSLStreamAdapterEvent(rtc::StreamInterface* stream, int sig, int err) {
if (sig & rtc::SE_READ) {
uint8_t buffer[4096] = "";
size_t read;
int error;
// Read data received from the client and store it in our internal
// buffer.
rtc::StreamResult r = stream->Read(buffer, read, error);
if (r == rtc::SR_SUCCESS) {
buffer[read] = '\0';
// Here we assume that the buffer is interpretable as string.
char* buffer_as_char = reinterpret_cast<char*>(buffer);
RTC_LOG(LS_INFO) << "Server received '" << buffer_as_char << "'";
data_ += buffer_as_char;
}
}
}
private:
void DoHandshake(rtc::Socket* socket) {
ssl_stream_adapter_ = rtc::SSLStreamAdapter::Create(
std::make_unique<rtc::SocketStream>(socket));
ssl_stream_adapter_->SetMode(ssl_mode_);
ssl_stream_adapter_->SetServerRole();
// SSLStreamAdapter is normally used for peer-to-peer communication, but
// here we're testing communication between a client and a server
// (e.g. a WebRTC-based application and an RFC 5766 TURN server), where
// clients are not required to provide a certificate during handshake.
// Accordingly, we must disable client authentication here.
ssl_stream_adapter_->SetClientAuthEnabledForTesting(false);
ssl_stream_adapter_->SetIdentity(ssl_identity_->Clone());
// Set a bogus peer certificate digest.
unsigned char digest[20];
size_t digest_len = sizeof(digest);
ssl_stream_adapter_->SetPeerCertificateDigest(rtc::DIGEST_SHA_1, digest,
digest_len);
ssl_stream_adapter_->StartSSL();
ssl_stream_adapter_->SignalEvent.connect(
this, &SSLAdapterTestDummyServer::OnSSLStreamAdapterEvent);
}
const rtc::SSLMode ssl_mode_;
std::unique_ptr<rtc::Socket> server_socket_;
std::unique_ptr<rtc::SSLStreamAdapter> ssl_stream_adapter_;
std::unique_ptr<rtc::SSLIdentity> ssl_identity_;
std::string data_;
};
class SSLAdapterTestBase : public ::testing::Test, public sigslot::has_slots<> {
public:
explicit SSLAdapterTestBase(const rtc::SSLMode& ssl_mode,
const rtc::KeyParams& key_params)
: ssl_mode_(ssl_mode),
vss_(new rtc::VirtualSocketServer()),
thread_(vss_.get()),
server_(new SSLAdapterTestDummyServer(ssl_mode_, key_params)),
client_(new SSLAdapterTestDummyClient(ssl_mode_)),
handshake_wait_(kTimeout) {}
void SetHandshakeWait(int wait) { handshake_wait_ = wait; }
void SetIgnoreBadCert(bool ignore_bad_cert) {
client_->SetIgnoreBadCert(ignore_bad_cert);
}
void SetCertVerifier(rtc::SSLCertificateVerifier* ssl_cert_verifier) {
client_->SetCertVerifier(ssl_cert_verifier);
}
void SetAlpnProtocols(const std::vector<std::string>& protos) {
client_->SetAlpnProtocols(protos);
}
void SetEllipticCurves(const std::vector<std::string>& curves) {
client_->SetEllipticCurves(curves);
}
void SetMockCertVerifier(bool return_value) {
auto mock_verifier = std::make_unique<MockCertVerifier>();
EXPECT_CALL(*mock_verifier, Verify(_)).WillRepeatedly(Return(return_value));
cert_verifier_ =
std::unique_ptr<rtc::SSLCertificateVerifier>(std::move(mock_verifier));
SetIgnoreBadCert(false);
SetCertVerifier(cert_verifier_.get());
}
void TestHandshake(bool expect_success) {
int rv;
// The initial state is CS_CLOSED
ASSERT_EQ(rtc::Socket::CS_CLOSED, client_->GetState());
rv = client_->Connect(server_->GetHostname(), server_->GetAddress());
ASSERT_EQ(0, rv);
// Now the state should be CS_CONNECTING
ASSERT_EQ(rtc::Socket::CS_CONNECTING, client_->GetState());
if (ssl_mode_ == rtc::SSL_MODE_DTLS) {
// For DTLS, call AcceptConnection() with the client's address.
server_->AcceptConnection(client_->GetAddress());
}
if (expect_success) {
// If expecting success, the client should end up in the CS_CONNECTED
// state after handshake.
EXPECT_EQ_WAIT(rtc::Socket::CS_CONNECTED, client_->GetState(),
handshake_wait_);
RTC_LOG(LS_INFO) << GetSSLProtocolName(ssl_mode_)
<< " handshake complete.";
} else {
// On handshake failure the client should end up in the CS_CLOSED state.
EXPECT_EQ_WAIT(rtc::Socket::CS_CLOSED, client_->GetState(),
handshake_wait_);
RTC_LOG(LS_INFO) << GetSSLProtocolName(ssl_mode_) << " handshake failed.";
}
}
void TestTransfer(absl::string_view message) {
int rv;
rv = client_->Send(message);
ASSERT_EQ(static_cast<int>(message.length()), rv);
// The server should have received the client's message.
EXPECT_EQ_WAIT(message, server_->GetReceivedData(), kTimeout);
rv = server_->Send(message);
ASSERT_EQ(static_cast<int>(message.length()), rv);
// The client should have received the server's message.
EXPECT_EQ_WAIT(message, client_->GetReceivedData(), kTimeout);
RTC_LOG(LS_INFO) << "Transfer complete.";
}
protected:
const rtc::SSLMode ssl_mode_;
std::unique_ptr<rtc::VirtualSocketServer> vss_;
rtc::AutoSocketServerThread thread_;
std::unique_ptr<SSLAdapterTestDummyServer> server_;
std::unique_ptr<SSLAdapterTestDummyClient> client_;
std::unique_ptr<rtc::SSLCertificateVerifier> cert_verifier_;
int handshake_wait_;
};
class SSLAdapterTestTLS_RSA : public SSLAdapterTestBase {
public:
SSLAdapterTestTLS_RSA()
: SSLAdapterTestBase(rtc::SSL_MODE_TLS, rtc::KeyParams::RSA()) {}
};
class SSLAdapterTestTLS_ECDSA : public SSLAdapterTestBase {
public:
SSLAdapterTestTLS_ECDSA()
: SSLAdapterTestBase(rtc::SSL_MODE_TLS, rtc::KeyParams::ECDSA()) {}
};
class SSLAdapterTestDTLS_RSA : public SSLAdapterTestBase {
public:
SSLAdapterTestDTLS_RSA()
: SSLAdapterTestBase(rtc::SSL_MODE_DTLS, rtc::KeyParams::RSA()) {}
};
class SSLAdapterTestDTLS_ECDSA : public SSLAdapterTestBase {
public:
SSLAdapterTestDTLS_ECDSA()
: SSLAdapterTestBase(rtc::SSL_MODE_DTLS, rtc::KeyParams::ECDSA()) {}
};
// Basic tests: TLS
// Test that handshake works, using RSA
TEST_F(SSLAdapterTestTLS_RSA, TestTLSConnect) {
TestHandshake(true);
}
// Test that handshake works with a custom verifier that returns true. RSA.
TEST_F(SSLAdapterTestTLS_RSA, TestTLSConnectCustomCertVerifierSucceeds) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
}
// Test that handshake fails with a custom verifier that returns false. RSA.
TEST_F(SSLAdapterTestTLS_RSA, TestTLSConnectCustomCertVerifierFails) {
SetMockCertVerifier(/*return_value=*/false);
TestHandshake(/*expect_success=*/false);
}
// Test that handshake works, using ECDSA
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSConnect) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
}
// Test that handshake works with a custom verifier that returns true. ECDSA.
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSConnectCustomCertVerifierSucceeds) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
}
// Test that handshake fails with a custom verifier that returns false. ECDSA.
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSConnectCustomCertVerifierFails) {
SetMockCertVerifier(/*return_value=*/false);
TestHandshake(/*expect_success=*/false);
}
// Test transfer between client and server, using RSA
TEST_F(SSLAdapterTestTLS_RSA, TestTLSTransfer) {
TestHandshake(true);
TestTransfer("Hello, world!");
}
// Test transfer between client and server, using RSA with custom cert verifier.
TEST_F(SSLAdapterTestTLS_RSA, TestTLSTransferCustomCertVerifier) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
TestTransfer("Hello, world!");
}
TEST_F(SSLAdapterTestTLS_RSA, TestTLSTransferWithBlockedSocket) {
TestHandshake(true);
// Tell the underlying socket to simulate being blocked.
vss_->SetSendingBlocked(true);
std::string expected;
int rv;
// Send messages until the SSL socket adapter starts applying backpressure.
// Note that this may not occur immediately since there may be some amount of
// intermediate buffering (either in our code or in BoringSSL).
for (int i = 0; i < 1024; ++i) {
std::string message = "Hello, world: " + rtc::ToString(i);
rv = client_->Send(message);
if (rv != static_cast<int>(message.size())) {
// This test assumes either the whole message or none of it is sent.
ASSERT_EQ(-1, rv);
break;
}
expected += message;
}
// Assert that the loop above exited due to Send returning -1.
ASSERT_EQ(-1, rv);
// Try sending another message while blocked. -1 should be returned again and
// it shouldn't end up received by the server later.
EXPECT_EQ(-1, client_->Send("Never sent"));
// Unblock the underlying socket. All of the buffered messages should be sent
// without any further action.
vss_->SetSendingBlocked(false);
EXPECT_EQ_WAIT(expected, server_->GetReceivedData(), kTimeout);
// Send another message. This previously wasn't working
std::string final_message = "Fin.";
expected += final_message;
EXPECT_EQ(static_cast<int>(final_message.size()),
client_->Send(final_message));
EXPECT_EQ_WAIT(expected, server_->GetReceivedData(), kTimeout);
}
// Test transfer between client and server, using ECDSA
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSTransfer) {
TestHandshake(true);
TestTransfer("Hello, world!");
}
// Test transfer between client and server, using ECDSA with custom cert
// verifier.
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSTransferCustomCertVerifier) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
TestTransfer("Hello, world!");
}
// Test transfer using ALPN with protos as h2 and http/1.1
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSALPN) {
std::vector<std::string> alpn_protos{"h2", "http/1.1"};
SetAlpnProtocols(alpn_protos);
TestHandshake(true);
TestTransfer("Hello, world!");
}
// Test transfer with TLS Elliptic curves set to "X25519:P-256:P-384:P-521"
TEST_F(SSLAdapterTestTLS_ECDSA, TestTLSEllipticCurves) {
std::vector<std::string> elliptic_curves{"X25519", "P-256", "P-384", "P-521"};
SetEllipticCurves(elliptic_curves);
TestHandshake(true);
TestTransfer("Hello, world!");
}
// Basic tests: DTLS
// Test that handshake works, using RSA
TEST_F(SSLAdapterTestDTLS_RSA, TestDTLSConnect) {
TestHandshake(true);
}
// Test that handshake works with a custom verifier that returns true. DTLS_RSA.
TEST_F(SSLAdapterTestDTLS_RSA, TestDTLSConnectCustomCertVerifierSucceeds) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
}
// Test that handshake fails with a custom verifier that returns false.
// DTLS_RSA.
TEST_F(SSLAdapterTestDTLS_RSA, TestTLSConnectCustomCertVerifierFails) {
SetMockCertVerifier(/*return_value=*/false);
TestHandshake(/*expect_success=*/false);
}
// Test that handshake works, using ECDSA
TEST_F(SSLAdapterTestDTLS_ECDSA, TestDTLSConnect) {
TestHandshake(true);
}
// Test that handshake works with a custom verifier that returns true.
// DTLS_ECDSA.
TEST_F(SSLAdapterTestDTLS_ECDSA, TestDTLSConnectCustomCertVerifierSucceeds) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
}
// Test that handshake fails with a custom verifier that returns false.
// DTLS_ECDSA.
TEST_F(SSLAdapterTestDTLS_ECDSA, TestTLSConnectCustomCertVerifierFails) {
SetMockCertVerifier(/*return_value=*/false);
TestHandshake(/*expect_success=*/false);
}
// Test transfer between client and server, using RSA
TEST_F(SSLAdapterTestDTLS_RSA, TestDTLSTransfer) {
TestHandshake(true);
TestTransfer("Hello, world!");
}
// Test transfer between client and server, using RSA with custom cert verifier.
TEST_F(SSLAdapterTestDTLS_RSA, TestDTLSTransferCustomCertVerifier) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
TestTransfer("Hello, world!");
}
// Test transfer between client and server, using ECDSA
TEST_F(SSLAdapterTestDTLS_ECDSA, TestDTLSTransfer) {
TestHandshake(true);
TestTransfer("Hello, world!");
}
// Test transfer between client and server, using ECDSA with custom cert
// verifier.
TEST_F(SSLAdapterTestDTLS_ECDSA, TestDTLSTransferCustomCertVerifier) {
SetMockCertVerifier(/*return_value=*/true);
TestHandshake(/*expect_success=*/true);
TestTransfer("Hello, world!");
}
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