Fix pattern signaling in seig for key rotation with cbcs

Closes #460.
Bug: 112769382

Change-Id: Id2277edf9ac1ca637354f3a585666ad139ed8ee2

packager/app/test/packager_test.py

@@ -1409,6 +1409,16 @@ def testLiveProfileAndKeyRotation(self):
         self._GetFlags(encryption=True, key_rotation=True, output_dash=True))
     self._CheckTestResults('live-profile-and-key-rotation')
 
+  def testLiveProfileAndKeyRotationCbcs(self):
+    self.assertPackageSuccess(
+        self._GetStreams(['audio', 'video'], segmented=True),
+        self._GetFlags(
+            encryption=True,
+            protection_scheme='cbcs',
+            key_rotation=True,
+            output_dash=True))
+    self._CheckTestResults('live-profile-and-key-rotation-cbcs')
+
   def testLiveProfileAndKeyRotationAndNoPsshInStream(self):
     self.assertPackageSuccess(
         self._GetStreams(['audio', 'video'], segmented=True),

packager/app/test/testdata/live-profile-and-key-rotation-cbcs/output.mpd

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--Generated with https://github.com/google/shaka-packager version <tag>-<hash>-<test>-->
+<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xlink="http://www.w3.org/1999/xlink" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd" xmlns:cenc="urn:mpeg:cenc:2013" profiles="urn:mpeg:dash:profile:isoff-live:2011" minBufferTime="PT2S" type="dynamic" publishTime="some_time" availabilityStartTime="some_time" minimumUpdatePeriod="PT5S" timeShiftBufferDepth="PT1800S">
+  <Period id="0" start="PT0S">
+    <AdaptationSet id="0" contentType="video" width="640" height="360" frameRate="30000/1001" segmentAlignment="true" par="16:9">
+      <ContentProtection value="cbcs" schemeIdUri="urn:mpeg:dash:mp4protection:2011"/>
+      <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b"/>
+      <Representation id="0" bandwidth="977527" codecs="avc1.64001e" mimeType="video/mp4" sar="1:1">
+        <SegmentTemplate timescale="30000" initialization="bear-640x360-video-init.mp4" media="bear-640x360-video-$Number$.m4s" startNumber="1">
+          <SegmentTimeline>
+            <S t="0" d="30030" r="1"/>
+            <S t="60060" d="22022"/>
+          </SegmentTimeline>
+        </SegmentTemplate>
+      </Representation>
+    </AdaptationSet>
+    <AdaptationSet id="1" contentType="audio" segmentAlignment="true">
+      <ContentProtection value="cbcs" schemeIdUri="urn:mpeg:dash:mp4protection:2011"/>
+      <ContentProtection schemeIdUri="urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b"/>
+      <Representation id="1" bandwidth="134336" codecs="mp4a.40.2" mimeType="audio/mp4" audioSamplingRate="44100">
+        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
+        <SegmentTemplate timescale="44100" initialization="bear-640x360-audio-init.mp4" media="bear-640x360-audio-$Number$.m4s" startNumber="1">
+          <SegmentTimeline>
+            <S t="0" d="45056"/>
+            <S t="45056" d="44032"/>
+            <S t="89088" d="31744"/>
+          </SegmentTimeline>
+        </SegmentTemplate>
+      </Representation>
+    </AdaptationSet>
+  </Period>
+</MPD>

packager/media/crypto/encryption_handler.cc

@@ -22,6 +22,7 @@
 #include "packager/media/codecs/vp8_parser.h"
 #include "packager/media/codecs/vp9_parser.h"
 #include "packager/media/crypto/sample_aes_ec3_cryptor.h"
+#include "packager/status_macros.h"
 
 namespace shaka {
 namespace media {
@@ -32,10 +33,17 @@ const size_t kCencBlockSize = 16u;
 // The encryption handler only supports a single output.
 const size_t kStreamIndex = 0;
 
-// The default KID for key rotation is all 0s.
+// The default KID, KEY and IV for key rotation are all 0s.
+// They are placeholders and are not really being used to encrypt data.
 const uint8_t kKeyRotationDefaultKeyId[] = {
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 };
+const uint8_t kKeyRotationDefaultKey[] = {
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+};
+const uint8_t kKeyRotationDefaultIv[] = {
+    0, 0, 0, 0, 0, 0, 0, 0,
+};
 
 // Adds one or more subsamples to |*decrypt_config|.  This may add more than one
 // if one of the values overflows the integer in the subsample.
@@ -179,25 +187,21 @@ Status EncryptionHandler::ProcessStreamInfo(const StreamInfo& clear_info) {
     }
   }
 
-  Status status = SetupProtectionPattern(stream_info->stream_type());
-  if (!status.ok())
-    return status;
+  RETURN_IF_ERROR(SetupProtectionPattern(stream_info->stream_type()));
 
   EncryptionKey encryption_key;
   const bool key_rotation_enabled = crypto_period_duration_ != 0;
   if (key_rotation_enabled) {
     check_new_crypto_period_ = true;
-    // Setup dummy key id and key to signal encryption for key rotation.
-    encryption_key.key_id.assign(
-        kKeyRotationDefaultKeyId,
-        kKeyRotationDefaultKeyId + sizeof(kKeyRotationDefaultKeyId));
-    // The key is not really used to encrypt any data. It is there just for
-    // convenience.
-    encryption_key.key = encryption_key.key_id;
+    // Setup dummy key id, key and iv to signal encryption for key rotation.
+    encryption_key.key_id.assign(std::begin(kKeyRotationDefaultKeyId),
+                                 std::end(kKeyRotationDefaultKeyId));
+    encryption_key.key.assign(std::begin(kKeyRotationDefaultKey),
+                              std::end(kKeyRotationDefaultKey));
+    encryption_key.iv.assign(std::begin(kKeyRotationDefaultIv),
+                             std::end(kKeyRotationDefaultIv));
   } else {
-    status = key_source_->GetKey(stream_label_, &encryption_key);
-    if (!status.ok())
-      return status;
+    RETURN_IF_ERROR(key_source_->GetKey(stream_label_, &encryption_key));
   }
   if (!CreateEncryptor(encryption_key))
     return Status(error::ENCRYPTION_FAILURE, "Failed to create encryptor");
@@ -233,10 +237,8 @@ Status EncryptionHandler::ProcessMediaSample(
     const int64_t current_crypto_period_index = dts / crypto_period_duration_;
     if (current_crypto_period_index != prev_crypto_period_index_) {
       EncryptionKey encryption_key;
-      Status status = key_source_->GetCryptoPeriodKey(
-          current_crypto_period_index, stream_label_, &encryption_key);
-      if (!status.ok())
-        return status;
+      RETURN_IF_ERROR(key_source_->GetCryptoPeriodKey(
+          current_crypto_period_index, stream_label_, &encryption_key));
       if (!CreateEncryptor(encryption_key))
         return Status(error::ENCRYPTION_FAILURE, "Failed to create encryptor");
       prev_crypto_period_index_ = current_crypto_period_index;
@@ -355,14 +357,13 @@ Status EncryptionHandler::SetupProtectionPattern(StreamType stream_type) {
         skip_byte_block_ = 9u;
       } else {
         // Tracks other than video are protected using whole-block full-sample
-        // encryption, which is essentially a pattern of 1:0. Note that this may
-        // not be the same as the non-pattern based encryption counterparts,
-        // e.g. in 'cens' for full sample encryption, the whole sample is
-        // encrypted up to the last 16-byte boundary, see 23001-7:2016(E) 9.7;
-        // while in 'cenc' for full sample encryption, the last partial 16-byte
-        // block is also encrypted, see 23001-7:2016(E) 9.4.2. Another
-        // difference is the use of constant iv.
-        crypt_byte_block_ = 1u;
+        // encryption. Note that this may not be the same as the non-pattern
+        // based encryption counterparts, e.g. in 'cens' whole-block full sample
+        // encryption, the whole sample is encrypted up to the last 16-byte
+        // boundary, see 23001-7:2016(E) 9.7; while in 'cenc' full sample
+        // encryption, the last partial 16-byte block is also encrypted, see
+        // 23001-7:2016(E) 9.4.2. Another difference is the use of constant iv.
+        crypt_byte_block_ = 0u;
         skip_byte_block_ = 0u;
       }
       break;

packager/media/crypto/encryption_handler_unittest.cc

@@ -406,7 +406,7 @@ class EncryptionHandlerEncryptionTest
         return 0;
       case FOURCC_cens:
       case FOURCC_cbcs:
-        return 1;
+        return codec_ == kCodecAAC ? 0 : 1;
       default:
         return 0;
     }

packager/media/formats/mp4/mp4_muxer.cc

@@ -114,11 +114,6 @@ void GenerateSinf(FourCC old_type,
       break;
     case FOURCC_cbcs:
     case FOURCC_cens:
-      if (track_encryption.default_skip_byte_block == 0) {
-        // Some clients, e.g. Safari v11.0.3 does not like having
-        // crypt_byte_block as a non-zero value when skip_byte_block is zero.
-        track_encryption.default_crypt_byte_block = 0;
-      }
       // CENCv3 10.3 ‘cens’ AES-CTR subsample pattern encryption scheme and
       //        10.4 ‘cbcs’ AES-CBC subsample pattern encryption scheme:
       // The version of the Track Encryption Box (‘tenc’) SHALL be 1.