const
  shifts2: array[0..15]of byte=
    (0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0);

  des_skb: array[0..7,0..63]of dword=(
    (
    (* for C bits (numbered as per FIPS 46) 1 2 3 4 5 6 *)
    $00000000,$00000010,$20000000,$20000010,
    $00010000,$00010010,$20010000,$20010010,
    $00000800,$00000810,$20000800,$20000810,
    $00010800,$00010810,$20010800,$20010810,
    $00000020,$00000030,$20000020,$20000030,
    $00010020,$00010030,$20010020,$20010030,
    $00000820,$00000830,$20000820,$20000830,
    $00010820,$00010830,$20010820,$20010830,
    $00080000,$00080010,$20080000,$20080010,
    $00090000,$00090010,$20090000,$20090010,
    $00080800,$00080810,$20080800,$20080810,
    $00090800,$00090810,$20090800,$20090810,
    $00080020,$00080030,$20080020,$20080030,
    $00090020,$00090030,$20090020,$20090030,
    $00080820,$00080830,$20080820,$20080830,
    $00090820,$00090830,$20090820,$20090830
    ),(
    (* for C bits (numbered as per FIPS 46) 7 8 10 11 12 13 *)
    $00000000,$02000000,$00002000,$02002000,
    $00200000,$02200000,$00202000,$02202000,
    $00000004,$02000004,$00002004,$02002004,
    $00200004,$02200004,$00202004,$02202004,
    $00000400,$02000400,$00002400,$02002400,
    $00200400,$02200400,$00202400,$02202400,
    $00000404,$02000404,$00002404,$02002404,
    $00200404,$02200404,$00202404,$02202404,
    $10000000,$12000000,$10002000,$12002000,
    $10200000,$12200000,$10202000,$12202000,
    $10000004,$12000004,$10002004,$12002004,
    $10200004,$12200004,$10202004,$12202004,
    $10000400,$12000400,$10002400,$12002400,
    $10200400,$12200400,$10202400,$12202400,
    $10000404,$12000404,$10002404,$12002404,
    $10200404,$12200404,$10202404,$12202404
    ),(
    (* for C bits (numbered as per FIPS 46) 14 15 16 17 19 20 *)
    $00000000,$00000001,$00040000,$00040001,
    $01000000,$01000001,$01040000,$01040001,
    $00000002,$00000003,$00040002,$00040003,
    $01000002,$01000003,$01040002,$01040003,
    $00000200,$00000201,$00040200,$00040201,
    $01000200,$01000201,$01040200,$01040201,
    $00000202,$00000203,$00040202,$00040203,
    $01000202,$01000203,$01040202,$01040203,
    $08000000,$08000001,$08040000,$08040001,
    $09000000,$09000001,$09040000,$09040001,
    $08000002,$08000003,$08040002,$08040003,
    $09000002,$09000003,$09040002,$09040003,
    $08000200,$08000201,$08040200,$08040201,
    $09000200,$09000201,$09040200,$09040201,
    $08000202,$08000203,$08040202,$08040203,
    $09000202,$09000203,$09040202,$09040203
    ),(
    (* for C bits (numbered as per FIPS 46) 21 23 24 26 27 28 *)
    $00000000,$00100000,$00000100,$00100100,
    $00000008,$00100008,$00000108,$00100108,
    $00001000,$00101000,$00001100,$00101100,
    $00001008,$00101008,$00001108,$00101108,
    $04000000,$04100000,$04000100,$04100100,
    $04000008,$04100008,$04000108,$04100108,
    $04001000,$04101000,$04001100,$04101100,
    $04001008,$04101008,$04001108,$04101108,
    $00020000,$00120000,$00020100,$00120100,
    $00020008,$00120008,$00020108,$00120108,
    $00021000,$00121000,$00021100,$00121100,
    $00021008,$00121008,$00021108,$00121108,
    $04020000,$04120000,$04020100,$04120100,
    $04020008,$04120008,$04020108,$04120108,
    $04021000,$04121000,$04021100,$04121100,
    $04021008,$04121008,$04021108,$04121108
    ),(
    (* for D bits (numbered as per FIPS 46) 1 2 3 4 5 6 *)
    $00000000,$10000000,$00010000,$10010000,
    $00000004,$10000004,$00010004,$10010004,
    $20000000,$30000000,$20010000,$30010000,
    $20000004,$30000004,$20010004,$30010004,
    $00100000,$10100000,$00110000,$10110000,
    $00100004,$10100004,$00110004,$10110004,
    $20100000,$30100000,$20110000,$30110000,
    $20100004,$30100004,$20110004,$30110004,
    $00001000,$10001000,$00011000,$10011000,
    $00001004,$10001004,$00011004,$10011004,
    $20001000,$30001000,$20011000,$30011000,
    $20001004,$30001004,$20011004,$30011004,
    $00101000,$10101000,$00111000,$10111000,
    $00101004,$10101004,$00111004,$10111004,
    $20101000,$30101000,$20111000,$30111000,
    $20101004,$30101004,$20111004,$30111004
    ),(
    (* for D bits (numbered as per FIPS 46) 8 9 11 12 13 14 *)
    $00000000,$08000000,$00000008,$08000008,
    $00000400,$08000400,$00000408,$08000408,
    $00020000,$08020000,$00020008,$08020008,
    $00020400,$08020400,$00020408,$08020408,
    $00000001,$08000001,$00000009,$08000009,
    $00000401,$08000401,$00000409,$08000409,
    $00020001,$08020001,$00020009,$08020009,
    $00020401,$08020401,$00020409,$08020409,
    $02000000,$0A000000,$02000008,$0A000008,
    $02000400,$0A000400,$02000408,$0A000408,
    $02020000,$0A020000,$02020008,$0A020008,
    $02020400,$0A020400,$02020408,$0A020408,
    $02000001,$0A000001,$02000009,$0A000009,
    $02000401,$0A000401,$02000409,$0A000409,
    $02020001,$0A020001,$02020009,$0A020009,
    $02020401,$0A020401,$02020409,$0A020409
    ),(
    (* for D bits (numbered as per FIPS 46) 16 17 18 19 20 21 *)
    $00000000,$00000100,$00080000,$00080100,
    $01000000,$01000100,$01080000,$01080100,
    $00000010,$00000110,$00080010,$00080110,
    $01000010,$01000110,$01080010,$01080110,
    $00200000,$00200100,$00280000,$00280100,
    $01200000,$01200100,$01280000,$01280100,
    $00200010,$00200110,$00280010,$00280110,
    $01200010,$01200110,$01280010,$01280110,
    $00000200,$00000300,$00080200,$00080300,
    $01000200,$01000300,$01080200,$01080300,
    $00000210,$00000310,$00080210,$00080310,
    $01000210,$01000310,$01080210,$01080310,
    $00200200,$00200300,$00280200,$00280300,
    $01200200,$01200300,$01280200,$01280300,
    $00200210,$00200310,$00280210,$00280310,
    $01200210,$01200310,$01280210,$01280310
    ),(
    (* for D bits (numbered as per FIPS 46) 22 23 24 25 27 28 *)
    $00000000,$04000000,$00040000,$04040000,
    $00000002,$04000002,$00040002,$04040002,
    $00002000,$04002000,$00042000,$04042000,
    $00002002,$04002002,$00042002,$04042002,
    $00000020,$04000020,$00040020,$04040020,
    $00000022,$04000022,$00040022,$04040022,
    $00002020,$04002020,$00042020,$04042020,
    $00002022,$04002022,$00042022,$04042022,
    $00000800,$04000800,$00040800,$04040800,
    $00000802,$04000802,$00040802,$04040802,
    $00002800,$04002800,$00042800,$04042800,
    $00002802,$04002802,$00042802,$04042802,
    $00000820,$04000820,$00040820,$04040820,
    $00000822,$04000822,$00040822,$04040822,
    $00002820,$04002820,$00042820,$04042820,
    $00002822,$04002822,$00042822,$04042822
    ));

  des_sptrans: array[0..7,0..63] of dword=(
    (
    (* nibble 0 *)
    $02080800, $00080000, $02000002, $02080802,
    $02000000, $00080802, $00080002, $02000002,
    $00080802, $02080800, $02080000, $00000802,
    $02000802, $02000000, $00000000, $00080002,
    $00080000, $00000002, $02000800, $00080800,
    $02080802, $02080000, $00000802, $02000800,
    $00000002, $00000800, $00080800, $02080002,
    $00000800, $02000802, $02080002, $00000000,
    $00000000, $02080802, $02000800, $00080002,
    $02080800, $00080000, $00000802, $02000800,
    $02080002, $00000800, $00080800, $02000002,
    $00080802, $00000002, $02000002, $02080000,
    $02080802, $00080800, $02080000, $02000802,
    $02000000, $00000802, $00080002, $00000000,
    $00080000, $02000000, $02000802, $02080800,
    $00000002, $02080002, $00000800, $00080802
    ),(
    (* nibble 1 *)
    $40108010, $00000000, $00108000, $40100000,
    $40000010, $00008010, $40008000, $00108000,
    $00008000, $40100010, $00000010, $40008000,
    $00100010, $40108000, $40100000, $00000010,
    $00100000, $40008010, $40100010, $00008000,
    $00108010, $40000000, $00000000, $00100010,
    $40008010, $00108010, $40108000, $40000010,
    $40000000, $00100000, $00008010, $40108010,
    $00100010, $40108000, $40008000, $00108010,
    $40108010, $00100010, $40000010, $00000000,
    $40000000, $00008010, $00100000, $40100010,
    $00008000, $40000000, $00108010, $40008010,
    $40108000, $00008000, $00000000, $40000010,
    $00000010, $40108010, $00108000, $40100000,
    $40100010, $00100000, $00008010, $40008000,
    $40008010, $00000010, $40100000, $00108000
    ),(
    (* nibble 2 *)
    $04000001, $04040100, $00000100, $04000101,
    $00040001, $04000000, $04000101, $00040100,
    $04000100, $00040000, $04040000, $00000001,
    $04040101, $00000101, $00000001, $04040001,
    $00000000, $00040001, $04040100, $00000100,
    $00000101, $04040101, $00040000, $04000001,
    $04040001, $04000100, $00040101, $04040000,
    $00040100, $00000000, $04000000, $00040101,
    $04040100, $00000100, $00000001, $00040000,
    $00000101, $00040001, $04040000, $04000101,
    $00000000, $04040100, $00040100, $04040001,
    $00040001, $04000000, $04040101, $00000001,
    $00040101, $04000001, $04000000, $04040101,
    $00040000, $04000100, $04000101, $00040100,
    $04000100, $00000000, $04040001, $00000101,
    $04000001, $00040101, $00000100, $04040000
    ),(
    (* nibble 3 *)
    $00401008, $10001000, $00000008, $10401008,
    $00000000, $10400000, $10001008, $00400008,
    $10401000, $10000008, $10000000, $00001008,
    $10000008, $00401008, $00400000, $10000000,
    $10400008, $00401000, $00001000, $00000008,
    $00401000, $10001008, $10400000, $00001000,
    $00001008, $00000000, $00400008, $10401000,
    $10001000, $10400008, $10401008, $00400000,
    $10400008, $00001008, $00400000, $10000008,
    $00401000, $10001000, $00000008, $10400000,
    $10001008, $00000000, $00001000, $00400008,
    $00000000, $10400008, $10401000, $00001000,
    $10000000, $10401008, $00401008, $00400000,
    $10401008, $00000008, $10001000, $00401008,
    $00400008, $00401000, $10400000, $10001008,
    $00001008, $10000000, $10000008, $10401000
    ),(
    (* nibble 4 *)
    $08000000, $00010000, $00000400, $08010420,
    $08010020, $08000400, $00010420, $08010000,
    $00010000, $00000020, $08000020, $00010400,
    $08000420, $08010020, $08010400, $00000000,
    $00010400, $08000000, $00010020, $00000420,
    $08000400, $00010420, $00000000, $08000020,
    $00000020, $08000420, $08010420, $00010020,
    $08010000, $00000400, $00000420, $08010400,
    $08010400, $08000420, $00010020, $08010000,
    $00010000, $00000020, $08000020, $08000400,
    $08000000, $00010400, $08010420, $00000000,
    $00010420, $08000000, $00000400, $00010020,
    $08000420, $00000400, $00000000, $08010420,
    $08010020, $08010400, $00000420, $00010000,
    $00010400, $08010020, $08000400, $00000420,
    $00000020, $00010420, $08010000, $08000020
    ),(
    (* nibble 5 *)
    $80000040, $00200040, $00000000, $80202000,
    $00200040, $00002000, $80002040, $00200000,
    $00002040, $80202040, $00202000, $80000000,
    $80002000, $80000040, $80200000, $00202040,
    $00200000, $80002040, $80200040, $00000000,
    $00002000, $00000040, $80202000, $80200040,
    $80202040, $80200000, $80000000, $00002040,
    $00000040, $00202000, $00202040, $80002000,
    $00002040, $80000000, $80002000, $00202040,
    $80202000, $00200040, $00000000, $80002000,
    $80000000, $00002000, $80200040, $00200000,
    $00200040, $80202040, $00202000, $00000040,
    $80202040, $00202000, $00200000, $80002040,
    $80000040, $80200000, $00202040, $00000000,
    $00002000, $80000040, $80002040, $80202000,
    $80200000, $00002040, $00000040, $80200040
    ),(
    (* nibble 6 *)
    $00004000, $00000200, $01000200, $01000004,
    $01004204, $00004004, $00004200, $00000000,
    $01000000, $01000204, $00000204, $01004000,
    $00000004, $01004200, $01004000, $00000204,
    $01000204, $00004000, $00004004, $01004204,
    $00000000, $01000200, $01000004, $00004200,
    $01004004, $00004204, $01004200, $00000004,
    $00004204, $01004004, $00000200, $01000000,
    $00004204, $01004000, $01004004, $00000204,
    $00004000, $00000200, $01000000, $01004004,
    $01000204, $00004204, $00004200, $00000000,
    $00000200, $01000004, $00000004, $01000200,
    $00000000, $01000204, $01000200, $00004200,
    $00000204, $00004000, $01004204, $01000000,
    $01004200, $00000004, $00004004, $01004204,
    $01000004, $01004200, $01004000, $00004004
    ),(
    (* nibble 7 *)
    $20800080, $20820000, $00020080, $00000000,
    $20020000, $00800080, $20800000, $20820080,
    $00000080, $20000000, $00820000, $00020080,
    $00820080, $20020080, $20000080, $20800000,
    $00020000, $00820080, $00800080, $20020000,
    $20820080, $20000080, $00000000, $00820000,
    $20000000, $00800000, $20020080, $20800080,
    $00800000, $00020000, $20820000, $00000080,
    $00800000, $00020000, $20000080, $20820080,
    $00020080, $20000000, $00000000, $00820000,
    $20800080, $20020080, $20020000, $00800080,
    $20820000, $00000080, $00800080, $20020000,
    $20820080, $00800000, $20800000, $20000080,
    $00820000, $00020080, $20020080, $20800000,
    $00000080, $20820000, $00820080, $00000000,
    $20000000, $20800080, $00020000, $00820080
    ));

procedure EncryptBlock(const InData; var OutData; KeyData: PDWordArray);
var
  l, r, t, u: dword;
  i: longint;
begin
  r:= PDword(@InData)^;
  l:= PDword(dword(@InData)+4)^;
  t:= ((l shr 4) xor r) and $0f0f0f0f;
  r:= r xor t;
  l:= l xor (t shl 4);
  t:= ((r shr 16) xor l) and $0000ffff;
  l:= l xor t;
  r:= r xor (t shl 16);
  t:= ((l shr 2) xor r) and $33333333;
  r:= r xor t;
  l:= l xor (t shl 2);
  t:= ((r shr 8) xor l) and $00ff00ff;
  l:= l xor t;
  r:= r xor (t shl 8);
  t:= ((l shr 1) xor r) and $55555555;
  r:= r xor t;
  l:= l xor (t shl 1);
  r:= (r shr 29) or (r shl 3);
  l:= (l shr 29) or (l shl 3);
  i:= 0;
  while i< 32 do
  begin
    u:= r xor KeyData^[i  ];
    t:= r xor KeyData^[i+1];
    t:= (t shr 4) or (t shl 28);
    l:= l xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    u:= l xor KeyData^[i+2];
    t:= l xor KeyData^[i+3];
    t:= (t shr 4) or (t shl 28);
    r:= r xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    u:= r xor KeyData^[i+4];
    t:= r xor KeyData^[i+5];
    t:= (t shr 4) or (t shl 28);
    l:= l xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    u:= l xor KeyData^[i+6];
    t:= l xor KeyData^[i+7];
    t:= (t shr 4) or (t shl 28);
    r:= r xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    Inc(i,8);
  end;
  r:= (r shr 3) or (r shl 29);
  l:= (l shr 3) or (l shl 29);
  t:= ((r shr 1) xor l) and $55555555;
  l:= l xor t;
  r:= r xor (t shl 1);
  t:= ((l shr 8) xor r) and $00ff00ff;
  r:= r xor t;
  l:= l xor (t shl 8);
  t:= ((r shr 2) xor l) and $33333333;
  l:= l xor t;
  r:= r xor (t shl 2);
  t:= ((l shr 16) xor r) and $0000ffff;
  r:= r xor t;
  l:= l xor (t shl 16);
  t:= ((r shr 4) xor l) and $0f0f0f0f;
  l:= l xor t;
  r:= r xor (t shl 4);
  PDword(@OutData)^:= l;
  PDword(dword(@OutData)+4)^:= r;
end;

procedure DecryptBlock(const InData; var OutData; KeyData: PDWordArray);
var
  l, r, t, u: dword;
  i: longint;
begin
  r:= PDword(@InData)^;
  l:= PDword(dword(@InData)+4)^;
  t:= ((l shr 4) xor r) and $0f0f0f0f;
  r:= r xor t;
  l:= l xor (t shl 4);
  t:= ((r shr 16) xor l) and $0000ffff;
  l:= l xor t;
  r:= r xor (t shl 16);
  t:= ((l shr 2) xor r) and $33333333;
  r:= r xor t;
  l:= l xor (t shl 2);
  t:= ((r shr 8) xor l) and $00ff00ff;
  l:= l xor t;
  r:= r xor (t shl 8);
  t:= ((l shr 1) xor r) and $55555555;
  r:= r xor t;
  l:= l xor (t shl 1);
  r:= (r shr 29) or (r shl 3);
  l:= (l shr 29) or (l shl 3);
  i:= 30;
  while i> 0 do
  begin
    u:= r xor KeyData^[i  ];
    t:= r xor KeyData^[i+1];
    t:= (t shr 4) or (t shl 28);
    l:= l xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    u:= l xor KeyData^[i-2];
    t:= l xor KeyData^[i-1];
    t:= (t shr 4) or (t shl 28);
    r:= r xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    u:= r xor KeyData^[i-4];
    t:= r xor KeyData^[i-3];
    t:= (t shr 4) or (t shl 28);
    l:= l xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    u:= l xor KeyData^[i-6];
    t:= l xor KeyData^[i-5];
    t:= (t shr 4) or (t shl 28);
    r:= r xor des_SPtrans[0,(u shr  2) and $3f] xor
              des_SPtrans[2,(u shr 10) and $3f] xor
              des_SPtrans[4,(u shr 18) and $3f] xor
              des_SPtrans[6,(u shr 26) and $3f] xor
              des_SPtrans[1,(t shr  2) and $3f] xor
              des_SPtrans[3,(t shr 10) and $3f] xor
              des_SPtrans[5,(t shr 18) and $3f] xor
              des_SPtrans[7,(t shr 26) and $3f];
    Dec(i,8);
  end;
  r:= (r shr 3) or (r shl 29);
  l:= (l shr 3) or (l shl 29);
  t:= ((r shr 1) xor l) and $55555555;
  l:= l xor t;
  r:= r xor (t shl 1);
  t:= ((l shr 8) xor r) and $00ff00ff;
  r:= r xor t;
  l:= l xor (t shl 8);
  t:= ((r shr 2) xor l) and $33333333;
  l:= l xor t;
  r:= r xor (t shl 2);
  t:= ((l shr 16) xor r) and $0000ffff;
  r:= r xor t;
  l:= l xor (t shl 16);
  t:= ((r shr 4) xor l) and $0f0f0f0f;
  l:= l xor t;
  r:= r xor (t shl 4);
  PDword(@OutData)^:= l;
  PDword(dword(@OutData)+4)^:= r;
end;