PKIHeaderBuilder

  PKIHeader ::= SEQUENCE {
            pvno                INTEGER     { cmp1999(1), cmp2000(2) },
            sender              GeneralName,
            -- identifies the sender
            recipient           GeneralName,
            -- identifies the intended recipient
            messageTime     [0] GeneralizedTime         OPTIONAL,
            -- time of production of this message (used when sender
            -- believes that the transport will be "suitable"; i.e.,
            -- that the time will still be meaningful upon receipt)
            protectionAlg   [1] AlgorithmIdentifier     OPTIONAL,
            -- algorithm used for calculation of protection bits
            senderKID       [2] KeyIdentifier           OPTIONAL,
            recipKID        [3] KeyIdentifier           OPTIONAL,
            -- to identify specific keys used for protection
            transactionID   [4] OCTET STRING            OPTIONAL,
            -- identifies the transaction; i.e., this will be the same in
            -- corresponding request, response, certConf, and PKIConf
            -- messages
            senderNonce     [5] OCTET STRING            OPTIONAL,
            recipNonce      [6] OCTET STRING            OPTIONAL,
            -- nonces used to provide replay protection, senderNonce
            -- is inserted by the creator of this message; recipNonce
            -- is a nonce previously inserted in a related message by
            -- the intended recipient of this message
            freeText        [7] PKIFreeText             OPTIONAL,
            -- this may be used to indicate context-specific instructions
            -- (this field is intended for human consumption)
            generalInfo     [8] SEQUENCE SIZE (1..MAX) OF
                                 InfoTypeAndValue     OPTIONAL
            -- this may be used to convey context-specific information
            -- (this field not primarily intended for human consumption)
 }