Add option to ignore mismatched HMACs when reading MXFs.

8 files changed, 20 insertions, 12 deletions

diff --git a/src/asset_reader.h b/src/asset_reader.h
index 2da67bd8..8478b51f 100644
--- a/src/asset_reader.h
+++ b/src/asset_reader.h
@@ -72,13 +72,17 @@ public:
 	std::shared_ptr<const F> get_frame (int n) const
 	{
 		/* Can't use make_shared here as the constructor is private */
-		return std::shared_ptr<const F> (new F(_reader, n, _crypto_context));
+		return std::shared_ptr<const F> (new F(_reader, n, _crypto_context, _check_hmac));
 	}
 
 	R* reader () const {
 		return _reader;
 	}
 
+	void set_check_hmac (bool check) {
+		_check_hmac = check;
+	}
+
 protected:
 	R* _reader = nullptr;
 	std::shared_ptr<DecryptionContext> _crypto_context;
@@ -100,6 +104,8 @@ private:
 			boost::throw_exception (FileError("could not open MXF file for reading", asset->file().get(), r));
 		}
 	}
+
+	bool _check_hmac = true;
 };
 
 
diff --git a/src/frame.h b/src/frame.h
index 74bd616f..01dfe8b4 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -54,12 +54,12 @@ template <class R, class B>
 class Frame
 {
 public:
-	Frame (R* reader, int n, std::shared_ptr<const DecryptionContext> c)
+	Frame (R* reader, int n, std::shared_ptr<const DecryptionContext> c, bool check_hmac)
 	{
 		/* XXX: unfortunate guesswork on this buffer size */
 		_buffer = std::make_shared<B>(Kumu::Megabyte);
 
-		if (ASDCP_FAILURE(reader->ReadFrame(n, *_buffer, c->context(), c->hmac()))) {
+		if (ASDCP_FAILURE(reader->ReadFrame(n, *_buffer, c->context(), check_hmac ? c->hmac() : nullptr))) {
 			boost::throw_exception (ReadError ("could not read frame"));
 		}
 	}
diff --git a/src/mono_picture_frame.cc b/src/mono_picture_frame.cc
index fb451e08..df75126c 100644
--- a/src/mono_picture_frame.cc
+++ b/src/mono_picture_frame.cc
@@ -80,13 +80,14 @@ MonoPictureFrame::MonoPictureFrame (boost::filesystem::path path)
  *  @param reader Reader for the asset's MXF file.
  *  @param n Frame within the asset, not taking EntryPoint into account.
  *  @param c Context for decryption, or 0.
+ *  @param check_hmac true to check the HMAC and give an error if it is not as expected.
  */
-MonoPictureFrame::MonoPictureFrame (ASDCP::JP2K::MXFReader* reader, int n, shared_ptr<DecryptionContext> c)
+MonoPictureFrame::MonoPictureFrame (ASDCP::JP2K::MXFReader* reader, int n, shared_ptr<DecryptionContext> c, bool check_hmac)
 {
 	/* XXX: unfortunate guesswork on this buffer size */
 	_buffer = make_shared<ASDCP::JP2K::FrameBuffer>(4 * Kumu::Megabyte);
 
-	auto const r = reader->ReadFrame (n, *_buffer, c->context(), c->hmac());
+	auto const r = reader->ReadFrame (n, *_buffer, c->context(), check_hmac ? c->hmac() : nullptr);
 
 	if (ASDCP_FAILURE(r)) {
 		boost::throw_exception (ReadError(String::compose ("could not read video frame %1 (%2)", n, static_cast<int>(r))));
diff --git a/src/mono_picture_frame.h b/src/mono_picture_frame.h
index 95b0d111..3ca16bf2 100644
--- a/src/mono_picture_frame.h
+++ b/src/mono_picture_frame.h
@@ -101,7 +101,7 @@ private:
 	*/
 	friend class AssetReader<ASDCP::JP2K::MXFReader, MonoPictureFrame>;
 
-	MonoPictureFrame (ASDCP::JP2K::MXFReader* reader, int n, std::shared_ptr<DecryptionContext>);
+	MonoPictureFrame (ASDCP::JP2K::MXFReader* reader, int n, std::shared_ptr<DecryptionContext>, bool check_hmac);
 
 	std::shared_ptr<ASDCP::JP2K::FrameBuffer> _buffer;
 };
diff --git a/src/sound_frame.cc b/src/sound_frame.cc
index 9c8087c2..25845d88 100644
--- a/src/sound_frame.cc
+++ b/src/sound_frame.cc
@@ -46,8 +46,8 @@ using std::cout;
 using namespace dcp;
 
 
-SoundFrame::SoundFrame (ASDCP::PCM::MXFReader* reader, int n, std::shared_ptr<const DecryptionContext> c)
-	: Frame<ASDCP::PCM::MXFReader, ASDCP::PCM::FrameBuffer> (reader, n, c)
+SoundFrame::SoundFrame (ASDCP::PCM::MXFReader* reader, int n, std::shared_ptr<const DecryptionContext> c, bool check_hmac)
+	: Frame<ASDCP::PCM::MXFReader, ASDCP::PCM::FrameBuffer> (reader, n, c, check_hmac)
 {
 	ASDCP::PCM::AudioDescriptor desc;
 	reader->FillAudioDescriptor (desc);
diff --git a/src/sound_frame.h b/src/sound_frame.h
index 85082299..0f5021e2 100644
--- a/src/sound_frame.h
+++ b/src/sound_frame.h
@@ -51,7 +51,7 @@ namespace dcp {
 class SoundFrame : public Frame<ASDCP::PCM::MXFReader, ASDCP::PCM::FrameBuffer>
 {
 public:
-	SoundFrame (ASDCP::PCM::MXFReader* reader, int n, std::shared_ptr<const DecryptionContext> c);
+	SoundFrame (ASDCP::PCM::MXFReader* reader, int n, std::shared_ptr<const DecryptionContext> c, bool check_hmac);
 	int channels () const;
 	int samples () const;
 	int32_t get (int channel, int sample) const;
diff --git a/src/stereo_picture_frame.cc b/src/stereo_picture_frame.cc
index 4cb9f2a1..8d3a2757 100644
--- a/src/stereo_picture_frame.cc
+++ b/src/stereo_picture_frame.cc
@@ -94,13 +94,14 @@ StereoPictureFrame::Part::size () const
 /** Make a picture frame from a 3D (stereoscopic) asset.
  *  @param reader Reader for the MXF file.
  *  @param n Frame within the asset, not taking EntryPoint into account.
+ *  @param check_hmac true to check the HMAC and give an error if it is not as expected.
  */
-StereoPictureFrame::StereoPictureFrame (ASDCP::JP2K::MXFSReader* reader, int n, shared_ptr<DecryptionContext> c)
+StereoPictureFrame::StereoPictureFrame (ASDCP::JP2K::MXFSReader* reader, int n, shared_ptr<DecryptionContext> c, bool check_hmac)
 {
 	/* XXX: unfortunate guesswork on this buffer size */
 	_buffer = make_shared<ASDCP::JP2K::SFrameBuffer>(4 * Kumu::Megabyte);
 
-	if (ASDCP_FAILURE (reader->ReadFrame (n, *_buffer, c->context(), c->hmac()))) {
+	if (ASDCP_FAILURE (reader->ReadFrame (n, *_buffer, c->context(), check_hmac ? c->hmac() : nullptr))) {
 		boost::throw_exception (ReadError (String::compose ("could not read video frame %1 of %2", n)));
 	}
 }
diff --git a/src/stereo_picture_frame.h b/src/stereo_picture_frame.h
index 096c821a..09d684c4 100644
--- a/src/stereo_picture_frame.h
+++ b/src/stereo_picture_frame.h
@@ -105,7 +105,7 @@ private:
 	*/
 	friend class AssetReader<ASDCP::JP2K::MXFSReader, StereoPictureFrame>;
 
-	StereoPictureFrame (ASDCP::JP2K::MXFSReader* reader, int n, std::shared_ptr<DecryptionContext>);
+	StereoPictureFrame (ASDCP::JP2K::MXFSReader* reader, int n, std::shared_ptr<DecryptionContext>, bool check_hmac);
 
 	std::shared_ptr<ASDCP::JP2K::SFrameBuffer> _buffer;
 };