Change WebRTC SslCipher to be exposed as number only.

webrtc/base/sslstreamadapter.h

Index: webrtc/base/sslstreamadapter.h
diff --git a/webrtc/base/sslstreamadapter.h b/webrtc/base/sslstreamadapter.h
index 4fb238a290482d13d00569bc57ccc5cdc45389f8..7db226c5ab60aea6b6d1dd18acf4e7ba5a049efb 100644
--- a/webrtc/base/sslstreamadapter.h
+++ b/webrtc/base/sslstreamadapter.h
@@ -19,6 +19,27 @@
 
 namespace rtc {
 
+// This follows https://tools.ietf.org/html/rfc5764#section-4.1.2.
+enum SrtpCipherType {
+  SrtpCipher_Unknown = 0,
+  SrtpCipher_AES_CM_128_HMAC_SHA1_80 = 1,
+  SrtpCipher_AES_CM_128_HMAC_SHA1_32 = 2,
+  SrtpCipher_NULL_HMAC_SHA1_80 = 5,
+  SrtpCipher_NULL_HMAC_SHA1_32 = 6,
+};
+
+// Convert SRTP Cipher's RFC names to its ID. TODO(guoweis): Investigate whether
+// there is existing definition already.
+SrtpCipherType GetSrtpCipherType(const std::string& cipher_rfc_name);
+
+// Cipher suite to use for SRTP. Typically a 80-bit HMAC will be used, except
+// in applications (voice) where the additional bandwidth may be significant.
+// A 80-bit HMAC is always used for SRTCP.
+// 128-bit AES with 80-bit SHA-1 HMAC.
+extern const char CS_AES_CM_128_HMAC_SHA1_80[];
+// 128-bit AES with 32-bit SHA-1 HMAC.
+extern const char CS_AES_CM_128_HMAC_SHA1_32[];
+
 // SSLStreamAdapter : A StreamInterfaceAdapter that does SSL/TLS.
 // After SSL has been started, the stream will only open on successful
 // SSL verification of certificates, and the communication is
@@ -135,7 +156,7 @@ class SSLStreamAdapter : public StreamAdapterInterface {
 
   // Retrieves the name of the cipher suite used for the connection
   // (e.g. "TLS_RSA_WITH_AES_128_CBC_SHA").
-  virtual bool GetSslCipher(std::string* cipher);
+  virtual bool GetSslCipher(uint16_t* cipher);
 
   // Key Exporter interface from RFC 5705
   // Arguments are:
@@ -167,9 +188,10 @@ class SSLStreamAdapter : public StreamAdapterInterface {
 
   // Returns the default Ssl cipher used between streams of this class
   // for the given protocol version. This is used by the unit tests.
-  // TODO(torbjorng@webrtc.org): Fix callers to avoid default parameter.
-  static std::string GetDefaultSslCipher(SSLProtocolVersion version,
-                                         KeyType key_type = KT_DEFAULT);
+  static uint16_t GetDefaultSslCipherForTest(SSLProtocolVersion version,
+                                             KeyType key_type);
+
+  static const std::string GetRfcSslCipherName(uint16_t cipher);

[davidben_webrtc, 2015/09/25 19:23:13]

const std::string -> std::string

const return types don't really do anything useful. (const references do, but I
don't think you want a const reference here.)

 
  private:
   // If true, the server certificate need not match the configured