Define SignData - DEPRECATED


Purpose

The SignData opcode adds support for digital signatures in WHIP! data. It is the wrapper opcode, wrapping the digital signature data, primarily intended to protect part or whole of the WHIP! data content. User applications will have to compute signatures for individual WHIP! data blocks (or cumulatively as a file) and embed signature information inside WHIP! data using this opcode. Syntax
 
Opcode format Opcode Operand Format Comments
Extended ASCII (SignData <ws><Iboolean signaling the presence/absence of Guid List opcode><ws><Guid Listblock ids list><ws><Isignature data size><ws><Byte *signature data>) -
Extended Binary 0x0166 <Byte'0' or '1' flag signalling the presence/absence of Guid List opcode><Guid List block ids list><Isignature data size><Byte *signature data>)+} -
Details Typically, at least the main drawing block should be protected in WHIP! data by the signature data. Alternatively, a user application can choose to protect a collection of blocks by making respective block ids as part of the Block List member and accounting for their respective block data in computing the signature information. The WHIP! data user application should signal the beginning of a "Signature" block by synching the Signature blockref rendition attribute before attempting to serialize Signature. Typically one SignData opcode should be serialized per signature. Multiple instances of SignData occurrences in a signature block(s) signifies that multiple signatures are applied to the same WHIP! data protecting the entire or partial WHIP! data content. Example
(SignData 1
   (GuidList 3
   (Guid 4092318655 15832 20440
         A1A7518FD4494438 )
   (Guid 4067110341 42419 19313
         95C91B9A639B1A23 )
   (Guid 924882196 5231 19171
         92BBB6F5868A67B1 ) ) 26
         6162636465666768696A6B6C6D6E6F707172737475767778797A )