Reliable and non-manipulatable processing of data streams in a receiver

Abstract

The invention provides a solution for secure and non-manipulatable processing of a data stream in a receiver, possibly in conjunction with a smartcard. A packet identity and a content type identifier associated with the packet identifier are received in encrypted form and securely processed within the receiver to allow an encrypted payload of the data stream to be processed without the possibility to manipulate the content type identifier in an attempt to intercept the payload after decryption.

1 - 21 . (canceled) 
     
     
         22 . A method in a receiver for processing a data stream, the method comprising:
 receiving the data stream including a payload and a first packet identifier associated with the payload;   receiving a second packet identifier and a first content type identifier associated with the second packet identifier;   comparing the first packet identifier with the second packet identifier to obtain a first comparison result; and   in response to the first comparison result, selecting a first decoding module from a plurality of decoding modules based on the first content type identifier to decode the payload.   
     
     
         23 . The method according to  claim 22 , comprising:
 comparing the first comparison result with a first condition; and   in response to determining that the first comparison result matches the first condition, executing the selection of the first decoding module from the plurality of decoding modules.   
     
     
         24 . The method according to  claim 22 , comprising:
 receiving a third packet identifier and a second content type identifier associated with the third packet identifier;   in response to determining that the first comparison result matches a second condition, comparing the first packet identifier with the third packet identifier to obtain a second comparison result for selection of a second decoding module from the plurality of decoding modules.   
     
     
         25 . The method according to  claim 24 , comprising:
 in response to determining that the second comparison result matches a third condition, selecting the second decoding module from the plurality of decoding modules based on the second content type identifier to decode the payload.   
     
     
         26 . The method according to  claim 24 , wherein receiving a third packet identifier and a second content type identifier comprises:
 receiving a clear text third packet identifier and a clear text second content type identifier associated with the clear text third packet identifier; and/or.   receiving the third packet identifier and the second content type identifier in a program map table in a MPEG2 transport stream   
     
     
         27 . The method according to  claim 26 , wherein receiving the data stream comprises:
 receiving the data stream comprising the payload and the header having the first packet identifier, the payload and the header being part of an elementary stream in a MPEG transport stream.   
     
     
         28 . The method according to  claim 22 , wherein receiving a second packet identifier and a first content type identifier comprises:
 receiving the second packet identifier and the first content type identifier in an encrypted form, from a secure environment.   
     
     
         29 . The method according to  claim 28 , wherein receiving a second packet identifier and a first content type identifier comprises:
 receiving the encrypted second packet identifier and the encrypted first content type identifier in an encrypted entitlement message; and   transmitting the encrypted entitlement message to a smartcard, the second packet identifier and the first content type identifier being provided from the smartcard over a secure connection.   
     
     
         30 . The method according to  claim 22 , wherein receiving a second packet identifier and a first content type identifier comprises:
 receiving the second packet identifier and the first content type identifier from a secure environment comprising either one or more of a hardcoded memory of the receiver and a smartcard.   
     
     
         31 . The method according to  claim 22 , comprising:
 selecting an interface from a plurality of interfaces based on the first content type identifier; and   restricting an output of the first decoding module to the selected interface.   
     
     
         32 . A receiver for processing a data stream, comprising:
 a processor configured to:
 receive the data stream including a payload and a first packet identifier associated with the payload, 
 receive a second packet identifier and a first content type identifier associated with the second packet identifier, and 
 compare the first packet identifier with the second packet identifier to obtain a first comparison result; and 
   a router configured to:
 in response to the first comparison result, select a first decoding module from a plurality of decoding modules based on the first content type identifier; and 
 route the payload to the first decoding module to decode the payload. 
   
     
     
         33 . The receiver according to  claim 32 , wherein the processor is configured to:
 compare the first comparison result with a first condition; and   in response to determining that the first comparison result matches the first condition, executing the selection of the first decoding module.   
     
     
         34 . The receiver according to  claim 32 , wherein the processor is configured to:
 receive a third packet identifier and a second content type identifier associated with the third packet identifier; and   in response to determining that the first comparison result matches a second condition, comparing the first packet identifier with the third packet identifier to obtain a second comparison result for selection of a second decoding module from the plurality of decoding modules.   
     
     
         35 . The receiver according to  claim 34 , wherein the processor is configured to:
 determine that the second comparison result matches a third condition to select the second decoding module from the plurality of decoding modules based on the second content type identifier to decode the payload.   
     
     
         36 . The receiver according to  claim 34 , wherein the processor is configured to:
 receive a clear text third packet identifier and a clear text second content type identifier associated with the clear text third packet identifier; and/or   receive the third packet identifier and the second content type identifier in a program map table in a MPEG2 transport stream   
     
     
         37 . The receiver according to  claim 32 , wherein the receiver receives the data stream comprising the payload and the header having the first packet identifier, the payload and the header being part of an elementary stream in a MPEG transport stream. 
     
     
         38 . The receiver according to  claim 34 , wherein either one or more of the first decoding module and the second decoding module comprises a video decoder, an audio decoder in a secured chipset of the receiver, a teletext decoder, a subtitling decoder and/or a software applet that is external to the secured chipset. 
     
     
         39 . The receiver according to  claim 32 , wherein the processor is configured to:
 receive the second packet identifier and the first content type identifier in an encrypted form, in an encrypted entitlement message; and   transmitting the encrypted entitlement message to a smartcard, the second packet identifier and the first content type identifier being provided from the smartcard over a secure connection.   
     
     
         40 . The receiver according to  claim 32 , wherein the processor is configured to:
 receive the second packet identifier and the first content type identifier from a secure environment comprising either one or more of a hardcoded memory of the receiver and a smartcard.   
     
     
         41 . The receiver according to  claim 32 , wherein the processor is configured to:
 select an interface from a plurality of interfaces based on the first content type identifier; and   restrict an output of the first decoding module to the selected interface.   
     
     
         42 . A computer readable storage medium storing one or more programs, the one or more programs comprising instructions, which when executed by a receiver with a computer processor, cause the receiver with the computer processor to perform a method comprising:
 receiving the data stream including a payload and a first packet identifier associated with the payload;   receiving a second packet identifier and a first content type identifier associated with the second packet identifier;   comparing the first packet identifier with the second packet identifier to obtain a first comparison result; and   in response to the first comparison result, selecting a first decoding module from a plurality of decoding modules based on the first content type identifier to decode the payload.