Add support for GCM cipher suites from RFC 7714.

talk/session/media/channel_unittest.cc

Index: talk/session/media/channel_unittest.cc
diff --git a/talk/session/media/channel_unittest.cc b/talk/session/media/channel_unittest.cc
index 6b1d66fe39c1408d96a6d658b100c4c0da4dbec8..bdd6fbc33de6dc471e51f5a92c51f2b26f8ce263 100644
--- a/talk/session/media/channel_unittest.cc
+++ b/talk/session/media/channel_unittest.cc
@@ -125,7 +125,7 @@ template<class T>
 class ChannelTest : public testing::Test, public sigslot::has_slots<> {
  public:
   enum Flags { RTCP = 0x1, RTCP_MUX = 0x2, SECURE = 0x4, SSRC_MUX = 0x8,
-               DTLS = 0x10 };
+               DTLS = 0x10, GCM_CIPHER = 0x20 };
 
   ChannelTest(bool verify_playout,
               const uint8_t* rtp_data,
@@ -153,11 +153,9 @@ class ChannelTest : public testing::Test, public sigslot::has_slots<> {
     media_channel1_ = ch1;
     media_channel2_ = ch2;
     channel1_.reset(CreateChannel(thread, &media_engine_, ch1,
-                                  &transport_controller1_,
-                                  (flags1 & RTCP) != 0));
+                                  &transport_controller1_, flags1));
     channel2_.reset(CreateChannel(thread, &media_engine_, ch2,
-                                  &transport_controller2_,
-                                  (flags2 & RTCP) != 0));
+                                  &transport_controller2_, flags2));
     channel1_->SignalMediaMonitor.connect(
         this, &ChannelTest<T>::OnMediaMonitor);
     channel2_->SignalMediaMonitor.connect(
@@ -205,9 +203,13 @@ class ChannelTest : public testing::Test, public sigslot::has_slots<> {
       cricket::MediaEngineInterface* engine,
       typename T::MediaChannel* ch,
       cricket::TransportController* transport_controller,
-      bool rtcp) {
+      int flags) {
     typename T::Channel* channel = new typename T::Channel(
-        thread, engine, ch, transport_controller, cricket::CN_AUDIO, rtcp);
+        thread, engine, ch, transport_controller, cricket::CN_AUDIO,
+        (flags & RTCP) != 0);
+    rtc::CryptoOptions crypto_options;
+    crypto_options.enable_gcm_crypto_suites = (flags & GCM_CIPHER) != 0;
+    channel->SetCryptoOptions(crypto_options);
     if (!channel->Init()) {
       delete channel;
       channel = NULL;
@@ -397,6 +399,20 @@ class ChannelTest : public testing::Test, public sigslot::has_slots<> {
   bool CheckNoRtcp2() {
     return media_channel2_->CheckNoRtcp();
   }
+  bool CheckGcmCipher(typename T::Channel* channel, int flags) {
+    int suite;
+    if (!channel->transport_channel()->GetSrtpCryptoSuite(&suite)) {
+      return false;
+    }
+
+    if (flags & GCM_CIPHER) {
+      return (suite == rtc::SRTP_AEAD_AES_128_GCM ||
+          suite == rtc::SRTP_AEAD_AES_256_GCM);
+    } else {
+      return (suite == rtc::SRTP_AES128_CM_SHA1_80 ||
+          suite == rtc::SRTP_AES128_CM_SHA1_32);
+    }
+  }
 
   void CreateContent(int flags,
                      const cricket::AudioCodec& audio_codec,
@@ -1244,8 +1260,8 @@ class ChannelTest : public testing::Test, public sigslot::has_slots<> {
   // Test that we properly send SRTP with RTCP in both directions.
   // You can pass in DTLS and/or RTCP_MUX as flags.
   void SendSrtpToSrtp(int flags1_in = 0, int flags2_in = 0) {
-    ASSERT((flags1_in & ~(RTCP_MUX | DTLS)) == 0);
-    ASSERT((flags2_in & ~(RTCP_MUX | DTLS)) == 0);
+    ASSERT((flags1_in & ~(RTCP_MUX | DTLS | GCM_CIPHER)) == 0);
+    ASSERT((flags2_in & ~(RTCP_MUX | DTLS | GCM_CIPHER)) == 0);
 
     int flags1 = RTCP | SECURE | flags1_in;
     int flags2 = RTCP | SECURE | flags2_in;
@@ -1262,6 +1278,10 @@ class ChannelTest : public testing::Test, public sigslot::has_slots<> {
     EXPECT_TRUE(channel2_->secure());
     EXPECT_EQ(dtls1 && dtls2, channel1_->secure_dtls());
     EXPECT_EQ(dtls1 && dtls2, channel2_->secure_dtls());
+    // A GCM cipher is only used if both channels support GCM ciphers.
+    int common_gcm_flags = (flags1 & GCM_CIPHER) & (flags2 & GCM_CIPHER);
+    EXPECT_TRUE(CheckGcmCipher(channel1_.get(), common_gcm_flags));
+    EXPECT_TRUE(CheckGcmCipher(channel2_.get(), common_gcm_flags));
     EXPECT_TRUE(SendRtp1());
     EXPECT_TRUE(SendRtp2());
     EXPECT_TRUE(SendRtcp1());
@@ -1863,9 +1883,13 @@ cricket::VideoChannel* ChannelTest<VideoTraits>::CreateChannel(
     cricket::MediaEngineInterface* engine,
     cricket::FakeVideoMediaChannel* ch,
     cricket::TransportController* transport_controller,
-    bool rtcp) {
+    int flags) {
   cricket::VideoChannel* channel = new cricket::VideoChannel(
-      thread, ch, transport_controller, cricket::CN_VIDEO, rtcp);
+      thread, ch, transport_controller, cricket::CN_VIDEO,
+        (flags & RTCP) != 0);
+  rtc::CryptoOptions crypto_options;
+  crypto_options.enable_gcm_crypto_suites = (flags & GCM_CIPHER) != 0;
+  channel->SetCryptoOptions(crypto_options);
   if (!channel->Init()) {
     delete channel;
     channel = NULL;
@@ -2085,6 +2109,21 @@ TEST_F(VoiceChannelTest, SendDtlsSrtpToDtlsSrtp) {
   Base::SendSrtpToSrtp(DTLS, DTLS);
 }
 
+TEST_F(VoiceChannelTest, SendDtlsSrtpToDtlsSrtpGcmBoth) {
+  MAYBE_SKIP_TEST(HaveDtlsSrtp);
+  Base::SendSrtpToSrtp(DTLS | GCM_CIPHER, DTLS | GCM_CIPHER);
+}
+
+TEST_F(VoiceChannelTest, SendDtlsSrtpToDtlsSrtpGcmOne) {
+  MAYBE_SKIP_TEST(HaveDtlsSrtp);
+  Base::SendSrtpToSrtp(DTLS | GCM_CIPHER, DTLS);
+}
+
+TEST_F(VoiceChannelTest, SendDtlsSrtpToDtlsSrtpGcmTwo) {
+  MAYBE_SKIP_TEST(HaveDtlsSrtp);
+  Base::SendSrtpToSrtp(DTLS, DTLS | GCM_CIPHER);
+}
+
 TEST_F(VoiceChannelTest, SendDtlsSrtpToDtlsSrtpRtcpMux) {
   MAYBE_SKIP_TEST(HaveDtlsSrtp);
   Base::SendSrtpToSrtp(DTLS | RTCP_MUX, DTLS | RTCP_MUX);
@@ -2421,6 +2460,21 @@ TEST_F(VideoChannelTest, SendDtlsSrtpToDtlsSrtp) {
   Base::SendSrtpToSrtp(DTLS, DTLS);
 }
 
+TEST_F(VideoChannelTest, SendDtlsSrtpToDtlsSrtpGcmBoth) {
+  MAYBE_SKIP_TEST(HaveDtlsSrtp);
+  Base::SendSrtpToSrtp(DTLS | GCM_CIPHER, DTLS | GCM_CIPHER);
+}
+
+TEST_F(VideoChannelTest, SendDtlsSrtpToDtlsSrtpGcmOne) {
+  MAYBE_SKIP_TEST(HaveDtlsSrtp);
+  Base::SendSrtpToSrtp(DTLS | GCM_CIPHER, DTLS);
+}
+
+TEST_F(VideoChannelTest, SendDtlsSrtpToDtlsSrtpGcmTwo) {
+  MAYBE_SKIP_TEST(HaveDtlsSrtp);
+  Base::SendSrtpToSrtp(DTLS, DTLS | GCM_CIPHER);
+}
+
 TEST_F(VideoChannelTest, SendDtlsSrtpToDtlsSrtpRtcpMux) {
   MAYBE_SKIP_TEST(HaveDtlsSrtp);
   Base::SendSrtpToSrtp(DTLS | RTCP_MUX, DTLS | RTCP_MUX);
@@ -2585,9 +2639,13 @@ cricket::DataChannel* ChannelTest<DataTraits>::CreateChannel(
     cricket::MediaEngineInterface* engine,
     cricket::FakeDataMediaChannel* ch,
     cricket::TransportController* transport_controller,
-    bool rtcp) {
+    int flags) {
   cricket::DataChannel* channel = new cricket::DataChannel(
-      thread, ch, transport_controller, cricket::CN_DATA, rtcp);
+      thread, ch, transport_controller, cricket::CN_DATA,
+        (flags & RTCP) != 0);
+  rtc::CryptoOptions crypto_options;
+  crypto_options.enable_gcm_crypto_suites = (flags & GCM_CIPHER) != 0;
+  channel->SetCryptoOptions(crypto_options);
   if (!channel->Init()) {
     delete channel;
     channel = NULL;