1 files changed, 69 insertions, 0 deletions
diff --git a/dom/media/webrtc/transport/SrtpFlow.h b/dom/media/webrtc/transport/SrtpFlow.h
new file mode 100644
index 0000000000..92fbfcf1a5
--- /dev/null
+++ b/dom/media/webrtc/transport/SrtpFlow.h
@@ -0,0 +1,69 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Original author: ekr@rtfm.com
+
+#ifndef srtpflow_h__
+#define srtpflow_h__
+
+#include "mozilla/RefPtr.h"
+#include "nsISupportsImpl.h"
+#include "srtp.h"
+
+namespace mozilla {
+
+#define SRTP_ICM_MASTER_KEY_LENGTH 16
+#define SRTP_ICM_MASTER_SALT_LENGTH 14
+#define SRTP_ICM_MAX_MASTER_LENGTH \
+  (SRTP_ICM_MASTER_KEY_LENGTH + SRTP_ICM_MASTER_SALT_LENGTH)
+
+#define SRTP_GCM_MASTER_KEY_MIN_LENGTH 16
+#define SRTP_GCM_MASTER_KEY_MAX_LENGTH 32
+#define SRTP_GCM_MASTER_SALT_LENGTH 12
+
+#define SRTP_GCM_MIN_MASTER_LENGTH \
+  (SRTP_GCM_MASTER_KEY_MIN_LENGTH + SRTP_GCM_MASTER_SALT_LENGTH)
+#define SRTP_GCM_MAX_MASTER_LENGTH \
+  (SRTP_GCM_MASTER_KEY_MAX_LENGTH + SRTP_GCM_MASTER_SALT_LENGTH)
+
+#define SRTP_MIN_KEY_LENGTH SRTP_GCM_MIN_MASTER_LENGTH
+#define SRTP_MAX_KEY_LENGTH SRTP_GCM_MAX_MASTER_LENGTH
+
+// SRTCP requires an auth tag *plus* a 4-byte index-plus-'E'-bit value (see
+// RFC 3711)
+#define SRTP_MAX_EXPANSION (SRTP_MAX_TRAILER_LEN + 4)
+
+class SrtpFlow {
+  ~SrtpFlow();
+
+ public:
+  static unsigned int KeySize(int cipher_suite);
+  static unsigned int SaltSize(int cipher_suite);
+
+  static RefPtr<SrtpFlow> Create(int cipher_suite, bool inbound,
+                                 const void* key, size_t key_len);
+
+  nsresult ProtectRtp(void* in, int in_len, int max_len, int* out_len);
+  nsresult UnprotectRtp(void* in, int in_len, int max_len, int* out_len);
+  nsresult ProtectRtcp(void* in, int in_len, int max_len, int* out_len);
+  nsresult UnprotectRtcp(void* in, int in_len, int max_len, int* out_len);
+
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(SrtpFlow)
+
+  static void srtp_event_handler(srtp_event_data_t* data);
+
+ private:
+  SrtpFlow() : session_(nullptr) {}
+
+  nsresult CheckInputs(bool protect, void* in, int in_len, int max_len,
+                       int* out_len);
+
+  static nsresult Init();
+  static bool initialized;  // Was libsrtp initialized? Only happens once.
+
+  srtp_t session_;
+};
+
+}  // namespace mozilla
+#endif