Initial import of Widevine Common Encryption DRM engine

Builds libwvmdrmengine.so, which is loaded by the new
MediaDrm APIs to support playback of Widevine/CENC
protected content.

Change-Id: I6f57dd37083dfd96c402cb9dd137c7d74edc8f1c

libwvdrmengine/cdm/core/include/crypto_session.h

@@ -0,0 +1,81 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// OEMCrypto Client - wrapper class for C-style OEMCrypto interface
+//
+#ifndef CDM_BASE_CRYPTO_SESSSION_H_
+#define CDM_BASE_CRYPTO_SESSSION_H_
+
+#include <string>
+#include <map>
+
+#include "crypto_key.h"
+#include "wv_cdm_types.h"
+
+namespace wvcdm {
+
+typedef std::map<CryptoKeyId,CryptoKey*> CryptoKeyMap;
+
+// TODO(gmorgan): fill out input and output descriptors
+typedef void* InputDescriptor;
+typedef void* OutputDescriptor;
+
+class CryptoSession {
+ public:
+  CryptoSession();
+  explicit CryptoSession(const std::string& sname);
+  ~CryptoSession();
+
+  bool Open();
+  void Close();
+
+  bool IsValid() { return valid_; }
+  bool IsOpen() { return open_; }
+  bool SuccessStatus();
+  CryptoResult session_status() { return session_status_; }
+  CryptoSessionId oec_session_id() { return oec_session_id_; }
+  CdmSessionId cdm_session_id() { return cdm_session_id_; }
+
+  // Key request/response
+  void GenerateRequestId(std::string& req_id_str);
+  bool PrepareRequest(const std::string& key_deriv_message,
+                      std::string* signature);
+  bool PrepareRenewalRequest(const std::string& message,
+                             std::string* signature);
+  bool LoadKeys(const std::string& message,
+                const std::string& signature,
+                const std::string& mac_key_iv,
+                const std::string& mac_key,
+                int num_keys,
+                const CryptoKey* key_array);
+  bool RefreshKeys(const std::string& message,
+                   const std::string& signature,
+                   int num_keys,
+                   const CryptoKey* key_array);
+  bool GenerateNonce(uint32_t* nonce);
+
+  // Media data path
+  bool SelectKey(const std::string& key_id);
+  bool Decrypt(const InputDescriptor input, OutputDescriptor output);
+
+ private:
+
+  void GenerateMacContext(const std::string& input_context,
+                          std::string* deriv_context);
+  void GenerateEncryptContext(const std::string& input_context,
+                              std::string* deriv_context);
+  size_t GetOffset(std::string message, std::string field);
+
+  bool valid_;
+  bool open_;
+  CdmSessionId cdm_session_id_;
+  CryptoSessionId oec_session_id_;
+  CryptoResult session_status_;
+
+  CryptoKeyMap keys_;
+
+  CORE_DISALLOW_COPY_AND_ASSIGN(CryptoSession);
+};
+
+}; // namespace wvcdm
+
+#endif  // CDM_BASE_CRYPTO_SESSSION_H_