Unify TLS cipher suite name handling

Move it away from the "proprietary" SSL_CIPHER_get_id and looking up the cipher based on that towards SSL_CIPHER_standard_name.

SSL_CIPHER_get_id and the associated GetSslCipherSuite API is kept around for
  WebRTC.PeerConnection.SslCipherSuite.*
UMA metrics and metrics compability (despite not yielding the IANA ids it promises).

BUG=None

Change-Id: Iaa357e3e31dc90abea688cf6ca10c0b40582ef38
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/363202
Reviewed-by: David Benjamin <davidben@webrtc.org>
Commit-Queue: Philipp Hancke <phancke@meta.com>
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#43097}

p2p/base/dtls_transport.cc

@@ -233,6 +233,13 @@ bool DtlsTransport::GetSslCipherSuite(int* cipher) {
   return dtls_->GetSslCipherSuite(cipher);
 }
 
+std::optional<absl::string_view> DtlsTransport::GetTlsCipherSuiteName() const {
+  if (dtls_state() != webrtc::DtlsTransportState::kConnected) {
+    return std::nullopt;
+  }
+  return dtls_->GetTlsCipherSuiteName();
+}
+
 webrtc::RTCError DtlsTransport::SetRemoteParameters(
     absl::string_view digest_alg,
     const uint8_t* digest,

p2p/base/dtls_transport.h

@@ -169,6 +169,7 @@ class DtlsTransport : public DtlsTransportInternal {
 
   // Find out which DTLS cipher was negotiated
   bool GetSslCipherSuite(int* cipher) override;
+  std::optional<absl::string_view> GetTlsCipherSuiteName() const override;
 
   // Once DTLS has been established, this method retrieves the certificate
   // chain in use by the remote peer, for use in external identity

p2p/base/dtls_transport_internal.h

@@ -70,6 +70,7 @@ class DtlsTransportInternal : public rtc::PacketTransportInternal {
   // Finds out which DTLS cipher was negotiated.
   // TODO(zhihuang): Remove this once all dependencies implement this.
   virtual bool GetSslCipherSuite(int* cipher) = 0;
+  virtual std::optional<absl::string_view> GetTlsCipherSuiteName() const = 0;
 
   // Find out which signature algorithm was used by the peer. Returns values
   // from

p2p/base/fake_dtls_transport.h

@@ -213,6 +213,10 @@ class FakeDtlsTransport : public DtlsTransportInternal {
   void SetSslCipherSuite(std::optional<int> cipher_suite) {
     ssl_cipher_suite_ = cipher_suite;
   }
+
+  std::optional<absl::string_view> GetTlsCipherSuiteName() const override {
+    return "FakeTlsCipherSuite";
+  }
   uint16_t GetSslPeerSignatureAlgorithm() const override { return 0; }
   rtc::scoped_refptr<rtc::RTCCertificate> GetLocalCertificate() const override {
     return local_cert_;

pc/jsep_transport.cc

@@ -642,6 +642,7 @@ bool JsepTransport::GetTransportStats(DtlsTransportInternal* dtls_transport,
   dtls_transport->GetSslVersionBytes(&substats.ssl_version_bytes);
   dtls_transport->GetSrtpCryptoSuite(&substats.srtp_crypto_suite);
   dtls_transport->GetSslCipherSuite(&substats.ssl_cipher_suite);
+  substats.tls_cipher_suite_name = dtls_transport->GetTlsCipherSuiteName();
   substats.dtls_state = dtls_transport->dtls_state();
   rtc::SSLRole dtls_role;
   if (dtls_transport->GetDtlsRole(&dtls_role)) {

pc/legacy_stats_collector.cc

@@ -1012,13 +1012,10 @@ void LegacyStatsCollector::ExtractSessionInfo_s(SessionStats& session_stats) {
             StatsReport::kStatsValueNameSrtpCipher,
             rtc::SrtpCryptoSuiteToName(srtp_crypto_suite));
       }
-      int ssl_cipher_suite = channel_iter.ssl_cipher_suite;
-      if (ssl_cipher_suite != rtc::kTlsNullWithNullNull &&
-          rtc::SSLStreamAdapter::SslCipherSuiteToName(ssl_cipher_suite)
-              .length()) {
+      if (channel_iter.tls_cipher_suite_name) {
         channel_report->AddString(
             StatsReport::kStatsValueNameDtlsCipher,
-            rtc::SSLStreamAdapter::SslCipherSuiteToName(ssl_cipher_suite));
+            std::string(*channel_iter.tls_cipher_suite_name));
       }
 
       // Collect stats for non-pooled candidates. Note that the reports

pc/legacy_stats_collector_unittest.cc

@@ -67,11 +67,6 @@ using ::testing::UnorderedElementsAre;
 
 namespace webrtc {
 
-namespace internal {
-// This value comes from openssl/tls1.h
-static const int TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA = 0xC014;
-}  // namespace internal
-
 // Error return values
 const char kNotFound[] = "NOT FOUND";
 
@@ -674,8 +669,7 @@ class LegacyStatsCollectorTest : public ::testing::Test {
     TransportChannelStats channel_stats;
     channel_stats.component = 1;
     channel_stats.srtp_crypto_suite = rtc::kSrtpAes128CmSha1_80;
-    channel_stats.ssl_cipher_suite =
-        internal::TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA;
+    channel_stats.tls_cipher_suite_name = "cipher_suite_for_test";
     pc->SetTransportStats(kTransportName, channel_stats);
 
     // Fake certificate to report.
@@ -722,9 +716,7 @@ class LegacyStatsCollectorTest : public ::testing::Test {
     std::string dtls_cipher_suite =
         ExtractStatsValue(StatsReport::kStatsReportTypeComponent, reports,
                           StatsReport::kStatsValueNameDtlsCipher);
-    EXPECT_EQ(rtc::SSLStreamAdapter::SslCipherSuiteToName(
-                  internal::TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA),
-              dtls_cipher_suite);
+    EXPECT_EQ(dtls_cipher_suite, "cipher_suite_for_test");
     std::string srtp_crypto_suite =
         ExtractStatsValue(StatsReport::kStatsReportTypeComponent, reports,
                           StatsReport::kStatsValueNameSrtpCipher);

pc/rtc_stats_collector.cc

@@ -1961,14 +1961,7 @@ void RTCStatsCollector::ProduceTransportStats_n(
         transport_stats->dtls_role = "unknown";
       }
 
-      if (channel_stats.ssl_cipher_suite != rtc::kTlsNullWithNullNull &&
-          rtc::SSLStreamAdapter::SslCipherSuiteToName(
-              channel_stats.ssl_cipher_suite)
-              .length()) {
-        transport_stats->dtls_cipher =
-            rtc::SSLStreamAdapter::SslCipherSuiteToName(
-                channel_stats.ssl_cipher_suite);
-      }
+      transport_stats->dtls_cipher = channel_stats.tls_cipher_suite_name;
       if (channel_stats.srtp_crypto_suite != rtc::kSrtpInvalidCryptoSuite &&
           rtc::SrtpCryptoSuiteToName(channel_stats.srtp_crypto_suite)
               .length()) {

pc/rtc_stats_collector_unittest.cc

@@ -2942,8 +2942,8 @@ TEST_F(RTCStatsCollectorTest, CollectRTCTransportStatsWithCrypto) {
       "thelocalufrag";
   rtp_transport_channel_stats.ice_transport_stats.ice_state =
       IceTransportState::kConnected;
-  // 0x2F is TLS_RSA_WITH_AES_128_CBC_SHA according to IANA
-  rtp_transport_channel_stats.ssl_cipher_suite = 0x2F;
+  rtp_transport_channel_stats.tls_cipher_suite_name =
+      "TLS_RSA_WITH_AES_128_CBC_SHA";
   rtp_transport_channel_stats.srtp_crypto_suite = rtc::kSrtpAes128CmSha1_80;
   pc_->SetTransportStats(kTransportName, {rtp_transport_channel_stats});
 

pc/transport_stats.h

@@ -31,6 +31,7 @@ struct TransportChannelStats {
   int ssl_version_bytes = 0;
   int srtp_crypto_suite = rtc::kSrtpInvalidCryptoSuite;
   int ssl_cipher_suite = rtc::kTlsNullWithNullNull;
+  std::optional<absl::string_view> tls_cipher_suite_name;
   std::optional<rtc::SSLRole> dtls_role;
   webrtc::DtlsTransportState dtls_state = webrtc::DtlsTransportState::kNew;
   IceTransportStats ice_transport_stats;

rtc_base/openssl_stream_adapter.cc

@@ -63,12 +63,6 @@
 #error "webrtc requires at least OpenSSL version 1.1.0, to support DTLS-SRTP"
 #endif
 
-// Defines for the TLS Cipher Suite Map.
-#define DEFINE_CIPHER_ENTRY_SSL3(name) \
-  { SSL3_CK_##name, "TLS_" #name }
-#define DEFINE_CIPHER_ENTRY_TLS1(name) \
-  { TLS1_CK_##name, "TLS_" #name }
-
 namespace rtc {
 namespace {
 using ::webrtc::SafeTask;
@@ -93,68 +87,6 @@ constexpr SrtpCipherMapEntry kSrtpCipherMap[] = {
     {"SRTP_AEAD_AES_128_GCM", kSrtpAeadAes128Gcm},
     {"SRTP_AEAD_AES_256_GCM", kSrtpAeadAes256Gcm}};
 
-#ifndef OPENSSL_IS_BORINGSSL
-// The "SSL_CIPHER_standard_name" function is only available in OpenSSL when
-// compiled with tracing, so we need to define the mapping manually here.
-constexpr SslCipherMapEntry kSslCipherMap[] = {
-    // TLS v1.0 ciphersuites from RFC2246.
-    DEFINE_CIPHER_ENTRY_SSL3(RSA_RC4_128_SHA),
-    {SSL3_CK_RSA_DES_192_CBC3_SHA, "TLS_RSA_WITH_3DES_EDE_CBC_SHA"},
-
-    // AES ciphersuites from RFC3268.
-    {TLS1_CK_RSA_WITH_AES_128_SHA, "TLS_RSA_WITH_AES_128_CBC_SHA"},
-    {TLS1_CK_DHE_RSA_WITH_AES_128_SHA, "TLS_DHE_RSA_WITH_AES_128_CBC_SHA"},
-    {TLS1_CK_RSA_WITH_AES_256_SHA, "TLS_RSA_WITH_AES_256_CBC_SHA"},
-    {TLS1_CK_DHE_RSA_WITH_AES_256_SHA, "TLS_DHE_RSA_WITH_AES_256_CBC_SHA"},
-
-    // ECC ciphersuites from RFC4492.
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_ECDSA_WITH_RC4_128_SHA),
-    {TLS1_CK_ECDHE_ECDSA_WITH_DES_192_CBC3_SHA,
-     "TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA"},
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_ECDSA_WITH_AES_128_CBC_SHA),
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_ECDSA_WITH_AES_256_CBC_SHA),
-
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_RSA_WITH_RC4_128_SHA),
-    {TLS1_CK_ECDHE_RSA_WITH_DES_192_CBC3_SHA,
-     "TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA"},
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_RSA_WITH_AES_128_CBC_SHA),
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_RSA_WITH_AES_256_CBC_SHA),
-
-    // TLS v1.2 ciphersuites.
-    {TLS1_CK_RSA_WITH_AES_128_SHA256, "TLS_RSA_WITH_AES_128_CBC_SHA256"},
-    {TLS1_CK_RSA_WITH_AES_256_SHA256, "TLS_RSA_WITH_AES_256_CBC_SHA256"},
-    {TLS1_CK_DHE_RSA_WITH_AES_128_SHA256,
-     "TLS_DHE_RSA_WITH_AES_128_CBC_SHA256"},
-    {TLS1_CK_DHE_RSA_WITH_AES_256_SHA256,
-     "TLS_DHE_RSA_WITH_AES_256_CBC_SHA256"},
-
-    // TLS v1.2 GCM ciphersuites from RFC5288.
-    DEFINE_CIPHER_ENTRY_TLS1(RSA_WITH_AES_128_GCM_SHA256),
-    DEFINE_CIPHER_ENTRY_TLS1(RSA_WITH_AES_256_GCM_SHA384),
-    DEFINE_CIPHER_ENTRY_TLS1(DHE_RSA_WITH_AES_128_GCM_SHA256),
-    DEFINE_CIPHER_ENTRY_TLS1(DHE_RSA_WITH_AES_256_GCM_SHA384),
-    DEFINE_CIPHER_ENTRY_TLS1(DH_RSA_WITH_AES_128_GCM_SHA256),
-    DEFINE_CIPHER_ENTRY_TLS1(DH_RSA_WITH_AES_256_GCM_SHA384),
-
-    // ECDH HMAC based ciphersuites from RFC5289.
-    {TLS1_CK_ECDHE_ECDSA_WITH_AES_128_SHA256,
-     "TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256"},
-    {TLS1_CK_ECDHE_ECDSA_WITH_AES_256_SHA384,
-     "TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384"},
-    {TLS1_CK_ECDHE_RSA_WITH_AES_128_SHA256,
-     "TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256"},
-    {TLS1_CK_ECDHE_RSA_WITH_AES_256_SHA384,
-     "TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384"},
-
-    // ECDH GCM based ciphersuites from RFC5289.
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_ECDSA_WITH_AES_128_GCM_SHA256),
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_ECDSA_WITH_AES_256_GCM_SHA384),
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_RSA_WITH_AES_128_GCM_SHA256),
-    DEFINE_CIPHER_ENTRY_TLS1(ECDHE_RSA_WITH_AES_256_GCM_SHA384),
-
-    {0, nullptr}};
-#endif  // #ifndef OPENSSL_IS_BORINGSSL
-
 #ifdef OPENSSL_IS_BORINGSSL
 // Enabled by EnableTimeCallbackForTesting. Should never be set in production
 // code.
@@ -388,23 +320,14 @@ bool OpenSSLStreamAdapter::SetPeerCertificateDigest(
   return true;
 }
 
-std::string OpenSSLStreamAdapter::SslCipherSuiteToName(int cipher_suite) {
-#ifdef OPENSSL_IS_BORINGSSL
-  const SSL_CIPHER* ssl_cipher = SSL_get_cipher_by_value(cipher_suite);
-  if (!ssl_cipher) {
-    return std::string();
+std::optional<absl::string_view> OpenSSLStreamAdapter::GetTlsCipherSuiteName()
+    const {
+  if (state_ != SSL_CONNECTED) {
+    return std::nullopt;
   }
-  return SSL_CIPHER_standard_name(ssl_cipher);
-#else
-  const int openssl_cipher_id = 0x03000000L | cipher_suite;
-  for (const SslCipherMapEntry* entry = kSslCipherMap; entry->rfc_name;
-       ++entry) {
-    if (openssl_cipher_id == static_cast<int>(entry->openssl_id)) {
-      return entry->rfc_name;
-    }
-  }
-  return std::string();
-#endif
+
+  const SSL_CIPHER* current_cipher = SSL_get_current_cipher(ssl_);
+  return SSL_CIPHER_standard_name(current_cipher);
 }
 
 bool OpenSSLStreamAdapter::GetSslCipherSuite(int* cipher_suite) {

rtc_base/openssl_stream_adapter.h

@@ -103,8 +103,7 @@ class OpenSSLStreamAdapter final : public SSLStreamAdapter,
   void Close() override;
   StreamState GetState() const override;
 
-  // TODO(guoweis): Move this away from a static class method.
-  static std::string SslCipherSuiteToName(int crypto_suite);
+  std::optional<absl::string_view> GetTlsCipherSuiteName() const override;
 
   bool GetSslCipherSuite(int* cipher) override;
   [[deprecated("Use GetSslVersionBytes")]] SSLProtocolVersion GetSslVersion()

rtc_base/ssl_stream_adapter.cc

@@ -119,9 +119,6 @@ bool SSLStreamAdapter::IsAcceptableCipher(absl::string_view cipher,
                                           KeyType key_type) {
   return OpenSSLStreamAdapter::IsAcceptableCipher(cipher, key_type);
 }
-std::string SSLStreamAdapter::SslCipherSuiteToName(int cipher_suite) {
-  return OpenSSLStreamAdapter::SslCipherSuiteToName(cipher_suite);
-}
 
 ///////////////////////////////////////////////////////////////////////////////
 // Test only settings

rtc_base/ssl_stream_adapter.h

@@ -185,6 +185,9 @@ class SSLStreamAdapter : public StreamInterface {
   // Retrieves the IANA registration id of the cipher suite used for the
   // connection (e.g. 0x2F for "TLS_RSA_WITH_AES_128_CBC_SHA").
   virtual bool GetSslCipherSuite(int* cipher_suite);
+  // Returns the name of the cipher suite used for the DTLS transport,
+  // as defined in the "Description" column of the IANA cipher suite registry.
+  virtual std::optional<absl::string_view> GetTlsCipherSuiteName() const = 0;
 
   // Retrieves the enum value for SSL version.
   // Will return -1 until the version has been negotiated.
@@ -236,11 +239,6 @@ class SSLStreamAdapter : public StreamInterface {
   static bool IsAcceptableCipher(int cipher, KeyType key_type);
   static bool IsAcceptableCipher(absl::string_view cipher, KeyType key_type);
 
-  // TODO(guoweis): Move this away from a static class method. Currently this is
-  // introduced such that any caller could depend on sslstreamadapter.h without
-  // depending on specific SSL implementation.
-  static std::string SslCipherSuiteToName(int cipher_suite);
-
   ////////////////////////////////////////////////////////////////////////////
   // Testing only member functions
   ////////////////////////////////////////////////////////////////////////////