Merge "Add cipher mode and pattern encryption support"

libwvdrmengine/cdm/core/include/crypto_key.h

@@ -17,6 +17,7 @@ class CryptoKey {
   const std::string& key_data_iv() const { return key_data_iv_; }
   const std::string& key_control() const { return key_control_; }
   const std::string& key_control_iv() const { return key_control_iv_; }
+  CdmCipherMode cipher_mode() const { return cipher_mode_; }
   void set_key_id(const std::string& key_id) { key_id_ = key_id; }
   void set_key_data(const std::string& key_data) { key_data_ = key_data; }
   void set_key_data_iv(const std::string& iv) { key_data_iv_ = iv; }
@@ -24,6 +25,9 @@ class CryptoKey {
   void set_key_control_iv(const std::string& ctl_iv) {
     key_control_iv_ = ctl_iv;
   }
+  void set_cipher_mode(CdmCipherMode cipher_mode) {
+    cipher_mode_ = cipher_mode;
+  }
 
   bool HasKeyControl() const { return key_control_.size() >= 16; }
 
@@ -33,6 +37,7 @@ class CryptoKey {
   std::string key_data_;
   std::string key_control_;
   std::string key_control_iv_;
+  CdmCipherMode cipher_mode_;
 };
 
 }  // namespace wvcdm

libwvdrmengine/cdm/core/include/wv_cdm_types.h

@@ -271,6 +271,26 @@ struct CdmHlsData {
   std::string uri;
 };
 
+enum CdmCipherMode {
+  kCipherModeCtr,
+  kCipherModeCbc,
+};
+
+// For schemes that do not use pattern encryption (cenc and cbc1), encrypt
+// and skip should be set to 0. For those that do (cens and cbcs), it is
+// recommended that encrypt+skip bytes sum to 10 and for cbcs that a 1:9
+// encrypt:skip ratio be used. See ISO/IEC DIS 23001-7, section 10.4.2 for
+// more information.
+struct CdmCencPatternEncryptionDescriptor {
+  size_t encrypt_blocks;  // number of 16 byte blocks to decrypt
+  size_t skip_blocks;     // number of 16 byte blocks to leave in clear
+  size_t offset_blocks;   // offset into the pattern for this call, in blocks
+  CdmCencPatternEncryptionDescriptor()
+      : encrypt_blocks(0),
+        skip_blocks(0),
+        offset_blocks(0) {}
+};
+
 struct CdmDecryptionParameters {
   bool is_encrypted;
   bool is_secure;
@@ -284,6 +304,7 @@ struct CdmDecryptionParameters {
   size_t decrypt_buffer_offset;
   uint8_t subsample_flags;
   bool is_video;
+  CdmCencPatternEncryptionDescriptor pattern_descriptor;
   CdmDecryptionParameters()
       : is_encrypted(true),
         is_secure(true),

libwvdrmengine/cdm/core/src/crypto_session.cpp

@@ -412,6 +412,9 @@ CdmResponseType CryptoSession::LoadKeys(
       ko->key_control_iv = NULL;
       ko->key_control = NULL;
     }
+    ko->cipher_mode = ki->cipher_mode() == kCipherModeCbc
+                          ? OEMCrypto_CipherMode_CBC
+                          : OEMCrypto_CipherMode_CTR;
   }
   uint8_t* pst = NULL;
   if (!provider_session_token.empty()) {
@@ -672,6 +675,10 @@ CdmResponseType CryptoSession::Decrypt(const CdmDecryptionParameters& params) {
                                &buffer_descriptor, params.subsample_flags);
   }
   if (params.is_encrypted || sts == OEMCrypto_ERROR_NOT_IMPLEMENTED) {
+    OEMCrypto_CENCEncryptPatternDesc pattern_descriptor;
+    pattern_descriptor.encrypt = params.pattern_descriptor.encrypt_blocks;
+    pattern_descriptor.skip = params.pattern_descriptor.skip_blocks;
+    pattern_descriptor.offset = params.pattern_descriptor.offset_blocks;
     AutoLock auto_lock(crypto_lock_);
     // Check if key needs to be selected
     if (params.is_encrypted) {
@@ -683,11 +690,10 @@ CdmResponseType CryptoSession::Decrypt(const CdmDecryptionParameters& params) {
         }
       }
     }
-    // TODO(rfrias): add encrypt pattern parameter.
     sts = OEMCrypto_DecryptCENC(
         oec_session_id_, params.encrypt_buffer, params.encrypt_length,
         params.is_encrypted, &(*params.iv).front(), params.block_offset,
-        &buffer_descriptor, NULL, params.subsample_flags);
+        &buffer_descriptor, &pattern_descriptor, params.subsample_flags);
   }
 
   switch (sts) {

libwvdrmengine/cdm/core/src/license.cpp

@@ -106,6 +106,9 @@ static std::vector<CryptoKey> ExtractContentKeys(const License& license) {
           key.set_key_control(license.key(i).key_control().key_control_block());
           key.set_key_control_iv(license.key(i).key_control().iv());
         }
+        // TODO(rfrias): Set cipher mode when the license protocol provides
+        // it (b/26190665). Set to default for now.
+        key.set_cipher_mode(kCipherModeCtr);
         key_array.push_back(key);
         break;
       case License_KeyContainer::KEY_CONTROL:

libwvdrmengine/cdm/include/wv_content_decryption_module.h

@@ -25,6 +25,7 @@ class WvContentDecryptionModule : public android::RefBase, public TimerHandler {
   static bool IsSupported(const std::string& init_data_type);
   static bool IsCenc(const std::string& init_data_type);
   static bool IsWebm(const std::string& init_data_type);
+  static bool IsHls(const std::string& init_data_type);
 
   // Session related methods
   virtual CdmResponseType OpenSession(const CdmKeySystem& key_system,

libwvdrmengine/cdm/src/wv_content_decryption_module.cpp

@@ -38,6 +38,10 @@ bool WvContentDecryptionModule::IsWebm(const std::string& init_data_type) {
   return InitializationData(init_data_type).is_webm();
 }
 
+bool WvContentDecryptionModule::IsHls(const std::string& init_data_type) {
+  return InitializationData(init_data_type).is_hls();
+}
+
 CdmResponseType WvContentDecryptionModule::OpenSession(
     const CdmKeySystem& key_system, CdmClientPropertySet* property_set,
     const std::string& origin, WvCdmEventListener* event_listener,