Accept all the media profiles required by JSEP.

JSEP section 5.1.3 states that:
  Any profile matching the following patterns MUST be accepted:
  "RTP/[S]AVP[F]" and "(UDP/TCP)/TLS/RTP/SAVP[F]"

NOTRY=True
BUG=webrtc:5638

Committed: https://crrev.com/b7f425ab68ec58e2a5beaaf5ef79f50f1982c6f9
Cr-Commit-Position: refs/heads/master@{#12338}

Review-Url: https://codereview.webrtc.org/1880913002
Cr-Commit-Position: refs/heads/master@{#12637}

webrtc/pc/mediasession.cc

@@ -1115,21 +1115,55 @@ static bool CreateMediaContentAnswer(
   return true;
 }
 
+static bool IsDtlsRtp(const std::string& protocol) {
+  // Most-likely values first.
+  return protocol == "UDP/TLS/RTP/SAVPF" || protocol == "TCP/TLS/RTP/SAVPF" ||
+         protocol == "UDP/TLS/RTP/SAVP" || protocol == "TCP/TLS/RTP/SAVP";
+}
+
+static bool IsPlainRtp(const std::string& protocol) {
+  // Most-likely values first.
+  return protocol == "RTP/SAVPF" || protocol == "RTP/AVPF" ||
+         protocol == "RTP/SAVP" || protocol == "RTP/AVP";
+}
+
+static bool IsDtlsSctp(const std::string& protocol) {
+  return protocol == "DTLS/SCTP";
+}
+
+static bool IsPlainSctp(const std::string& protocol) {
+  return protocol == "SCTP";
+}
+
 static bool IsMediaProtocolSupported(MediaType type,
                                      const std::string& protocol,
                                      bool secure_transport) {
-  // Data channels can have a protocol of SCTP or SCTP/DTLS.
-  if (type == MEDIA_TYPE_DATA &&
-      ((protocol == kMediaProtocolSctp && !secure_transport)||
-       (protocol == kMediaProtocolDtlsSctp && secure_transport))) {
+  // Since not all applications serialize and deserialize the media protocol,
+  // we will have to accept |protocol| to be empty.
+  if (protocol.empty()) {
     return true;
   }
 
-  // Since not all applications serialize and deserialize the media protocol,
-  // we will have to accept |protocol| to be empty.
-  return protocol == kMediaProtocolAvpf || protocol.empty() ||
-      protocol == kMediaProtocolSavpf ||
-      (protocol == kMediaProtocolDtlsSavpf && secure_transport);
+  if (type == MEDIA_TYPE_DATA) {
+    // Check for SCTP, but also for RTP for RTP-based data channels.
+    // TODO(pthatcher): Remove RTP once RTP-based data channels are gone.
+    if (secure_transport) {
+      // Most likely scenarios first.
+      return IsDtlsSctp(protocol) || IsDtlsRtp(protocol) ||
+             IsPlainRtp(protocol);
+    } else {
+      return IsPlainSctp(protocol) || IsPlainRtp(protocol);
+    }
+  }
+
+  // Allow for non-DTLS RTP protocol even when using DTLS because that's what
+  // JSEP specifies.
+  if (secure_transport) {
+    // Most likely scenarios first.
+    return IsDtlsRtp(protocol) || IsPlainRtp(protocol);
+  } else {
+    return IsPlainRtp(protocol);
+  }
 }
 
 static void SetMediaProtocol(bool secure_transport,

webrtc/pc/mediasession_unittest.cc

@@ -170,6 +170,12 @@ static const char kDataTrack1[] = "data_1";
 static const char kDataTrack2[] = "data_2";
 static const char kDataTrack3[] = "data_3";
 
+static const char* kMediaProtocols[] = {"RTP/AVP", "RTP/SAVP", "RTP/AVPF",
+                                        "RTP/SAVPF"};
+static const char* kMediaProtocolsDtls[] = {
+    "TCP/TLS/RTP/SAVPF", "TCP/TLS/RTP/SAVP", "UDP/TLS/RTP/SAVPF",
+    "UDP/TLS/RTP/SAVP"};
+
 static bool IsMediaContentOfType(const ContentInfo* content,
                                  MediaType media_type) {
   const MediaContentDescription* mdesc =
@@ -2379,3 +2385,62 @@ TEST_F(MediaSessionDescriptionFactoryTest,
   EXPECT_EQ("video_modified", video_content->name);
   EXPECT_EQ("data_modified", data_content->name);
 }
+
+class MediaProtocolTest : public ::testing::TestWithParam<const char*> {
+ public:
+  MediaProtocolTest() : f1_(&tdf1_), f2_(&tdf2_) {
+    f1_.set_audio_codecs(MAKE_VECTOR(kAudioCodecs1));
+    f1_.set_video_codecs(MAKE_VECTOR(kVideoCodecs1));
+    f1_.set_data_codecs(MAKE_VECTOR(kDataCodecs1));
+    f2_.set_audio_codecs(MAKE_VECTOR(kAudioCodecs2));
+    f2_.set_video_codecs(MAKE_VECTOR(kVideoCodecs2));
+    f2_.set_data_codecs(MAKE_VECTOR(kDataCodecs2));
+    f1_.set_secure(SEC_ENABLED);
+    f2_.set_secure(SEC_ENABLED);
+    tdf1_.set_certificate(rtc::RTCCertificate::Create(
+        rtc::scoped_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id1"))));
+    tdf2_.set_certificate(rtc::RTCCertificate::Create(
+        rtc::scoped_ptr<rtc::SSLIdentity>(new rtc::FakeSSLIdentity("id2"))));
+    tdf1_.set_secure(SEC_ENABLED);
+    tdf2_.set_secure(SEC_ENABLED);
+  }
+
+ protected:
+  MediaSessionDescriptionFactory f1_;
+  MediaSessionDescriptionFactory f2_;
+  TransportDescriptionFactory tdf1_;
+  TransportDescriptionFactory tdf2_;
+};
+
+TEST_P(MediaProtocolTest, TestAudioVideoAcceptance) {
+  MediaSessionOptions opts;
+  opts.recv_video = true;
+  std::unique_ptr<SessionDescription> offer(f1_.CreateOffer(opts, nullptr));
+  ASSERT_TRUE(offer.get() != nullptr);
+  // Set the protocol for all the contents.
+  for (auto content : offer.get()->contents()) {
+    static_cast<MediaContentDescription*>(content.description)
+        ->set_protocol(GetParam());
+  }
+  std::unique_ptr<SessionDescription> answer(
+      f2_.CreateAnswer(offer.get(), opts, nullptr));
+  const ContentInfo* ac = answer->GetContentByName("audio");
+  const ContentInfo* vc = answer->GetContentByName("video");
+  ASSERT_TRUE(ac != nullptr);
+  ASSERT_TRUE(vc != nullptr);
+  EXPECT_FALSE(ac->rejected);  // the offer is accepted
+  EXPECT_FALSE(vc->rejected);
+  const AudioContentDescription* acd =
+      static_cast<const AudioContentDescription*>(ac->description);
+  const VideoContentDescription* vcd =
+      static_cast<const VideoContentDescription*>(vc->description);
+  EXPECT_EQ(GetParam(), acd->protocol());
+  EXPECT_EQ(GetParam(), vcd->protocol());
+}
+
+INSTANTIATE_TEST_CASE_P(MediaProtocolPatternTest,
+                        MediaProtocolTest,
+                        ::testing::ValuesIn(kMediaProtocols));
+INSTANTIATE_TEST_CASE_P(MediaProtocolDtlsPatternTest,
+                        MediaProtocolTest,
+                        ::testing::ValuesIn(kMediaProtocolsDtls));