Added support for buffered CAM decryption

5 files changed, 48 insertions, 17 deletions

diff --git a/ci.c b/ci.c
index 2d9735e5..e2881fed 100644
--- a/ci.c
+++ b/ci.c
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: ci.c 3.3 2014/01/01 12:33:27 kls Exp $
+ * $Id: ci.c 3.4 2014/01/02 10:31:12 kls Exp $
  */
 
 #include "ci.h"
@@ -2014,8 +2014,10 @@ bool cCamSlot::IsDecrypting(void)
   return false;
 }
 
-void cCamSlot::Decrypt(uchar *Data, int Count)
+uchar *cCamSlot::Decrypt(uchar *Data, int &Count)
 {
+  Count = TS_SIZE;
+  return Data;
 }
 
 // --- cChannelCamRelation ---------------------------------------------------
diff --git a/ci.h b/ci.h
index 1d6f5d1f..11237121 100644
--- a/ci.h
+++ b/ci.h
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: ci.h 3.2 2014/01/01 12:13:04 kls Exp $
+ * $Id: ci.h 3.3 2014/01/02 10:14:39 kls Exp $
  */
 
 #ifndef __CI_H
@@ -235,19 +235,33 @@ public:
        ///< Clears the list of CA_PMT entries and tells the CAM to stop decrypting.
   virtual bool IsDecrypting(void);
        ///< Returns true if the CAM in this slot is currently used for decrypting.
-  virtual void Decrypt(uchar *Data, int Count);
+  virtual uchar *Decrypt(uchar *Data, int &Count);
        ///< If this is a CAM slot that can be freely assigned to any device,
        ///< but will not be directly inserted into the full TS data stream
        ///< in hardware, it can implement this function to be given access
        ///< to the data in the device's TS buffer. Data points to a buffer
-       ///< of Count bytes of TS packets. The first byte in Data is guaranteed
-       ///< to be a TS_SYNC_BYTE. This function may decrypt as many TS packets
-       ///< in Data as it wants, but it must decrypt at least the very first
-       ///< TS packet. Only this very first TS packet will be further processed
-       ///< after the call to this function. The next call will be done with
-       ///< Data pointing to the TS packet immediately following the previous
-       ///< one. However, it can not be assumed that a call to Decrypt() with
-       ///< a Data pointer of P will be followed by a call with P + TS_SIZE.
+       ///< of Count bytes of TS data. The first byte in Data is guaranteed
+       ///< to be a TS_SYNC_BYTE.
+       ///< There are three possible ways a CAM can handle decryption:
+       ///< 1. If the full TS data is physically routed through the CAM in hardware,
+       ///< there is no need to reimplement this function.
+       ///< The default implementation simply sets Count to TS_SIZE and returns Data.
+       ///< 2. If the CAM works directly on Data and decrypts the TS "in place" it
+       ///< shall decrypt at least the very first TS packet in Data, set Count to
+       ///< TS_SIZE and return Data. It may decrypt as many TS packets in Data as it
+       ///< wants, but it must decrypt at least the very first TS packet. Only this
+       ///< very first TS packet will be further processed after the call to this
+       ///< function. The next call will be done with Data pointing to the TS packet
+       ///< immediately following the previous one.
+       ///< 3. If the CAM needs to copy the data into a buffer of its own, and/or send
+       ///< the data to some file handle for processing and later retrieval, it shall
+       ///< set Count to the number of bytes it has read from Data and return a pointer
+       ///< to the next available decrypted TS packet (which will *not* be in the
+       ///< memory area pointed to by Data, but rather in some buffer that is under
+       ///< the CAM's control). If no decrypted TS packet is currently available, NULL
+       ///< shall be returned. If no data from Data can currently be processed, Count
+       ///< shall be set to 0 and the same Data pointer will be offered in the next
+       ///< call to Decrypt().
        ///< A derived class that implements this function will also need
        ///< to set the ReceiveCaPids parameter in the call to the base class
        ///< constructor to true in order to receive the CA pid data.
diff --git a/device.c b/device.c
index 4db3ddd7..84caf4e1 100644
--- a/device.c
+++ b/device.c
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: device.c 3.6 2014/01/01 11:51:17 kls Exp $
+ * $Id: device.c 3.7 2014/01/02 10:31:58 kls Exp $
  */
 
 #include "device.h"
@@ -1791,3 +1791,9 @@ uchar *cTSBuffer::Get(int *Available)
      }
   return NULL;
 }
+
+void cTSBuffer::Skip(int Count)
+{
+  ringBuffer->Del(Count);
+  delivered = false;
+}
diff --git a/device.h b/device.h
index 1cbd6cc9..368d5cfa 100644
--- a/device.h
+++ b/device.h
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: device.h 3.7 2013/12/28 12:59:13 kls Exp $
+ * $Id: device.h 3.8 2014/01/02 10:47:08 kls Exp $
  */
 
 #ifndef __DEVICE_H
@@ -837,6 +837,13 @@ public:
      ///< there are at least TS_SIZE bytes in the buffer. Otherwise NULL will be
      ///< returned and the value in Available (if given) is undefined.
      ///< Each call to Get() returns a pointer to the next TS packet in the buffer.
+  void Skip(int Count);
+     ///< If after a call to Get() more or less than TS_SIZE of the available data
+     ///< has been processed, a call to Skip() with the number of processed bytes
+     ///< will disable the automatic incrementing of the data pointer as described
+     ///< in Get() and skip the given number of bytes instead. Count may be 0 if the
+     ///< caller wants the previous TS packet to be delivered again in the next call
+     ///< to Get().
   };
 
 #endif //__DEVICE_H
diff --git a/dvbdevice.c b/dvbdevice.c
index 481489b3..62f29dac 100644
--- a/dvbdevice.c
+++ b/dvbdevice.c
@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: dvbdevice.c 3.7 2014/01/01 14:14:32 kls Exp $
+ * $Id: dvbdevice.c 3.8 2014/01/02 10:30:15 kls Exp $
  */
 
 #include "dvbdevice.h"
@@ -1673,8 +1673,10 @@ bool cDvbDevice::GetTSPacket(uchar *&Data)
   if (tsBuffer) {
      int Available;
      Data = tsBuffer->Get(&Available);
-     if (Data && CamSlot())
-        CamSlot()->Decrypt(Data, Available);
+     if (Data && CamSlot()) {
+        Data = CamSlot()->Decrypt(Data, Available);
+        tsBuffer->Skip(Available);
+        }
      return true;
      }
   return false;