SHABK | Back to Index page

| Prolog Control Block Contents SHABK DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

SHABK Prolog | Top of page

     NAME       : HCPSHABK
     DESCRIPTION: Secure Hash Algorithm parameter block
     DSECT      : SHABK
     FUNCTION   : Used to exchange information between the secure hash
      lgorithm checksum function in HCPSHA and callers of the function.
     LOCATED BY : ????
     CREATED BY : ???
     DELETED BY :
     REFERENCES : None
     SERIALIZED : ??
     RELOCATION CONSIDERATIONS : None
     COMPATIBILITY AND MIGRATION CONCERNS : ???????

SHABK Control Block Content | Top of page

     SHABK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      SHABK          Secure Hash Algorithm parameter block
    0000    0 Bitstring   28 SHAPARM (0)    Parameter block for KIMD/KLMD
    0000    0 Bitstring   20 SHA1SUM        This field holds the checksum of
                                            the data after a successfull call
                                            to HCPSHASM. If the caller is
                                            calling HCPSHASM multiple times
                                            in "intermediate mode" then this
                                            field is used to store a partial
                                            checksum between calls. The
                                            caller should always initially
                                            call HCPSHASM with this field set
                                            to all 00's.
    0014   20 Bitstring    8 SHAMBL         Message bit length. Set to 0
                                            initially. If the caller is
                                            calling HCPSHASM multiple times
                                            in "intermediate mode" then this
                                            field will be updated to hold the
                                            total message bit length for each
                                            call. The caller will not need to
                                            examine/modify this value other
                                            than to set it to 0 initially.
                                            This field is part of the KLMD
                                            parameter block.
    001C   28 Signed       4 SHADLEN        Length of the data pointed to by
                                            SHADATA in bytes. In final mode
                                            the data length can be any length
                                            supported by the KLMD
                                            instruction. In intermediate mode
                                            the data length MUST be a
                                            multiple of 64.
    0020   32 Signed       4 SHADATA        Host logical address of the data
                                            that HCPSHASM should use to
                                            calculate the SHA-1 sum. In final
                                            mode this data can be any length
                                            supported by the KLMD
                                            instruction. In intermediate mode
                                            the data length MUST be a
                                            multiple of 64.
    0024   36 Bitstring    1 SHAMODE        This is a code field that defines
                                            which mode HCPSHASM should
                                            operate in. The defined values
                                            are SHAFINAL and SHAINTER.
                                            SHAINTER is used for intermediate
                                            calls to HCPSHASM and SHAFINAL is
                                            used for the final call (or the
                                            *only* call if not using
                                            intermediate mode). See the
                                            prolog of HCPSHASM for more
                                            details.
              00000000       SHAFINAL       0 SHAFINAL Indicates that
                                            HCPSHASM should operate in final
                                            mode. See HCPSHASM prolog for
                                            details.
              00000001       SHAINTER       1 SHAINTER Indicates that
                                            HCPSHASM should operate in
                                            intermediate mode. See HCPSHASM
                                            prolog for details.
    0025   37 Bitstring    3 *              RESERVED FOR IBM USE
              00000005       SHASIZE        (*-SHABK+7)/8 size in double
                                            words
              00000028       SHABSIZE       SHASIZE*8 size in bytes

SHABK Storage Layout | Top of page

    *** SHABK - Secure Hash Algorithm parameter block
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                       SHA1SUM                         =
    *     |                           +---------------------------+
    *     |                           |         SHAMBL-           |
    *     +---------------------------+---------------------------+
    *  18 |          -(014)           |         SHADLEN           |
    *     +---------------------------+------+--------------------+
    *  20 |         SHADATA           |:MODE |////////////////////|
    *     +---------------------------+------+--------------------+
    *  28
    *
    *** SHABK - Secure Hash Algorithm parameter block

SHABK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    SHABSIZE       0025 00000028
    SHADATA        0020
    SHADLEN        001C
    SHAFINAL       0024 00000000
    SHAINTER       0024 00000001
    SHAMBL         0014
    SHAMODE        0024
    SHAPARM        0000
    SHASIZE        0025 00000005
    SHA1SUM        0000

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:30:29 EDT.
Copyright IBM Corporation, 1990, 2020