BLOWFISH

SUBROUTINE BLOWFISH(MODE, SVAL, MAT DTA, ERR)
* ************************************************** *
* ************************************************** *
* Blowfish is a 64 bit symmetric block cipher with a *
* variable length key of up to 448 bits (56 bytes),  *
* designed by Bruce Schneier.                        *
*                                                    *
* The algorithm is in the public domain.             *
*                                                    *
* References:                                        *
*   Bruce Schneier, "Section 14.3 Blowfish,"         *
*     Applied Cryptography, 2nd edition              *
*     John Wiley & Sons, 1996                    *
*                                                    *
*   Bruce Schneier, "Description of a New Variable-  *
*     Length Key, 64-Bit Cipher (Blowfish),"         *
*     Fast Software Encryption Cambridge Security    *
*     Workshop Proceedings,                          *
*     Springer-Verlag, 1004, pp 191-204.             *
*                                                    *
* Params: MODE     - Requested action. One of:       *
*                    0 = Generate session key and    *
*                        session S-box data using    *
*                        user key passed in 'SVAL'   *
*                    1 = ECB encrypt of 8 data bytes *
*                        passed in 'DTA'. Return the *
*                        encrypted 8 bytes in 'DTA'  *
*                    2 = ECB decrypt of 8 data bytes *
*                        passed in 'DTA'. Return the *
*                        decrypted 8 bytes in 'DTA'  *
*                    3 = CBC encrypt of the string   *
*                        passed in 'SVAL', using the *
*                        contents of 'DTA' as the IV *
*                        data. Return encrypted data *
*                        string in 'SVAL'.           *
*                    4 = CBC decrypt of the string   *
*                        passed in 'SVAL', using the *
*                        contents of 'DTA' as the IV *
*                        data. Return decrypted data *
*                        string in 'SVAL'.           *
*         SVAL     - String used for input/output if *
*                    'MODE' one of 0, 3 or 4         *
*         DTA      - Array used to pass data in/out  *
*                    when 'MODE' = 1, or to pass the *
*                    IV values when 'MODE' = 3 or 4  *
*         ERR      - Error flag. Set to zero if no   *
*                    error detected, else set to a   *
*                    non-zero code to reflect the    *
*                    error type. Might be one of:    *
*                    1 = User key too short when     *
*                        'MODE' = 1                  *
*                    2 = Invalid value for 'MODE'    *
*                        (ie: unknown action code)   *
*                                                    *
* NB: As this code assumes 'named common' is valid   *
* for the target platform, this code is not suitable *
* for older Pick{like} platforms (eg: R83)    (dmm)  *
*                                                    *
* 9 Sept 2001 - Fixed problem with BITXOR Universe   *
*               functions working differently on     *
*               some platforms when input values are *
*               large (ie: Bit 31 set)               *
* ************************************************** *
* ************************************************** *
   *
   EQU ROUNDS       TO 16         ;* Number of 'rounds'
   EQU MIN$KEY$LEN  TO 5          ;* Min acceptable key length (in chars)
   EQU MAX$KEY$LEN  TO 56         ;* Max key length (in chars)
   *
   EQU MAX32        TO 4294967295 ;* 0xFFFFFFFF
   EQU M32P1        TO 4294967296 ;* 0xFFFFFFFF + 1
   EQU MAXINT       TO 2147483647 ;* 0X7FFFFFFF
   EQU P2TO24       TO 16777216   ;* 2^24
   EQU P2TO16       TO 65536      ;* 2^16
   EQU P2TO8        TO 256        ;* 2^8
   *
   EQU GENKEY       TO 0          ;* Initialise session with key
   EQU ENCRYPT      TO 1          ;* Encrypt 8 bytes of data
   EQU DECRYPT      TO 2          ;* Decrypt 8 bytes of data
   EQU ENC$CBC      TO 3          ;* Encrypt SVAL in CBC mode
   EQU DEC$CBC      TO 4          ;* Decrypt SVAL in CBC mode
   *
   EQU NO$ERROR     TO 0          ;* Error code for 'no error'
   EQU INVALID$KEY  TO 1          ;* Error - User key to short
   EQU INVALID$MODE TO 2          ;* Error - Invalid value for 'MODE'
   *
   * Preserve session key & S-boxes in common! Note: 'PBKEY' is
   * dimensioned to 'ROUNDS' + 2
   COMMON /B$FISH/ PKEY(18), SKEY(1024)
   *
   DIM DTA(8)                     ;* Input/Output byte array
   *
   ERR = NO$ERROR                 ;* Assume no error!
   BEGIN CASE
      CASE MODE = ENCRYPT
         GOSUB 100
      CASE MODE = DECRYPT
         GOSUB 100
      CASE MODE = ENC$CBC
         GOSUB 500
      CASE MODE = DEC$CBC
         GOSUB 600
      CASE MODE = GENKEY
         GOSUB 900
      CASE 1
         * Error - Unknown request!
         ERR = INVALID$MODE
   END CASE
   RETURN
   *
* ************************************************************** *
* Convert 8 bytes of input into 2 32 bit values 'LEFT' & 'RIGHT' *
* pass these to either the decrypt or encrypt functions based on *
* the value of 'MODE'. On return, break these values back into 8 *
* byte values representing the encrypted/decrypted input bytes.  *
* ************************************************************** *
100*
   LEFT  = ((DTA(1) * 256 + DTA(2)) * 256 + DTA(3)) * 256 + DTA(4)
   RIGHT = ((DTA(5) * 256 + DTA(6)) * 256 + DTA(7)) * 256 + DTA(8)
   IF MODE = ENCRYPT THEN
      GOSUB 200
   END ELSE
      GOSUB 300
   END
   DTA(1) = INT(LEFT / P2TO24)
   DTA(2) = MOD(INT(LEFT / P2TO16), P2TO8)
   DTA(3) = MOD(INT(LEFT / P2TO8), P2TO8)
   DTA(4) = MOD(LEFT, P2TO8)
   DTA(5) = INT(RIGHT / P2TO24)
   DTA(6) = MOD(INT(RIGHT / P2TO16), P2TO8)
   DTA(7) = MOD(INT(RIGHT / P2TO8), P2TO8)
   DTA(8) = MOD(RIGHT, P2TO8)
   RETURN
   *
* ********************************************************* *
* Encryption. Passed to 32 bit blocks in 'LEFT' and 'RIGHT' *
* apply the Blowfish cipher function and return the output  *
* as 2 32 bit blocks, in the same variables.                *
* ********************************************************* *
200*
   R    = 1
   VAL  = LEFT
   VAL1 = PKEY(R)
   GOSUB 400
   LEFT = VAL
   LOOP
      A = MOD(INT(LEFT / P2TO24), P2TO8) + 1
      B = MOD(INT(LEFT / P2TO16), P2TO8) + 257
      C = MOD(INT(LEFT / P2TO8), P2TO8)  + 513
      D = MOD(LEFT, P2TO8)               + 769
      VAL  = SKEY(A) + SKEY(B)
      VAL1 = SKEY(C)
      GOSUB 400
      VAL = VAL + SKEY(D)
      R = R + 1
      VAL1 = PKEY(R)
      GOSUB 400
      VAL1 = RIGHT
      GOSUB 400
      RIGHT = VAL
      A = MOD(INT(RIGHT / P2TO24), P2TO8) + 1
      B = MOD(INT(RIGHT / P2TO16), P2TO8) + 257
      C = MOD(INT(RIGHT / P2TO8), P2TO8)  + 513
      D = MOD(RIGHT, P2TO8)               + 769
      VAL  = SKEY(A) + SKEY(B)
      VAL1 = SKEY(C)
      GOSUB 400
      VAL = VAL + SKEY(D)
      R = R + 1
      VAL1 = PKEY(R)
      GOSUB 400
      VAL1 = LEFT
      GOSUB 400
      LEFT = VAL
   WHILE R < ROUNDS DO REPEAT
   VAL  = RIGHT
   VAL1 = PKEY(R + 1)
   GOSUB 400
   RIGHT = LEFT
   LEFT = VAL
   RETURN
   *
* ********************************************************* *
* Decryption. Passed to 32 bit blocks in 'LEFT' and 'RIGHT' *
* apply the Blowfish cipher function in reverse order, and  *
* return in the same variables the decrypted output.        *
* ********************************************************* *
300*
   R    = ROUNDS + 2
   VAL  = LEFT
   VAL1 = PKEY(R)
   GOSUB 400
   LEFT = VAL
   LOOP
      A = MOD(INT(LEFT / P2TO24), P2TO8) + 1
      B = MOD(INT(LEFT / P2TO16), P2TO8) + 257
      C = MOD(INT(LEFT / P2TO8), P2TO8)  + 513
      D = MOD(LEFT, P2TO8)               + 769
      VAL  = SKEY(A) + SKEY(B)
      VAL1 = SKEY(C)
      GOSUB 400
      VAL = VAL + SKEY(D)
      R = R - 1
      VAL1 = PKEY(R)
      GOSUB 400
      VAL1 = RIGHT
      GOSUB 400
      RIGHT = VAL
      A = MOD(INT(RIGHT / P2TO24), P2TO8) + 1
      B = MOD(INT(RIGHT / P2TO16), P2TO8) + 257
      C = MOD(INT(RIGHT / P2TO8), P2TO8)  + 513
      D = MOD(RIGHT, P2TO8)               + 769
      VAL  = SKEY(A) + SKEY(B)
      VAL1 = SKEY(C)
      GOSUB 400
      VAL = VAL + SKEY(D)
      R = R - 1
      VAL1 = PKEY(R)
      GOSUB 400
      VAL1 = LEFT
      GOSUB 400
      LEFT = VAL
   WHILE R > 2 DO REPEAT
   VAL  = RIGHT
   VAL1 = PKEY(1)
   GOSUB 400
   RIGHT = LEFT
   LEFT = VAL
   RETURN
   *
* ********************************************* *
* Logical 'XOR' of two values. Both are assumed *
* to be unsigned 32 bit integers. Passed 'VAL'  *
* and 'VAL1', with result returned in 'VAL'     *
* NB: 'VAL' can be > 2^32-1 on entry, so result *
* is truncated to 32 bits for return as req'd.  *
* ********************************************* *
400*
   IF VAL > MAXINT OR VAL1 > MAXINT THEN
      VAL3 = BITXOR(MOD(VAL, P2TO16), MOD(VAL1, P2TO16))
      VAL4 = BITXOR(INT(VAL / P2TO16), INT(VAL1 / P2TO16))
      VAL = (VAL4 * P2TO16) + VAL3
      * As VAL can acutally exceed 32 bits, we need the next line!
      IF VAL > MAX32 THEN VAL = MOD(VAL, M32P1)
   END ELSE
      VAL = BITXOR(VAL, VAL1)
   END
   RETURN
   *
* ************************************************ *
* Encrypt a string passed in 'SVAL' using Blowfish *
* in CBC mode. IV data passed in array 'DTA'       *
* Note that we pad input to multiple of 8 bytes by *
* adding 0x00 characters as required.              *
* ************************************************ *
500*
   * Initialise 'LEFT' & 'RIGHT' as IV values from DTA!
   LEFT  = ((DTA(1) * 256 + DTA(2)) * 256 + DTA(3)) * 256 + DTA(4)
   RIGHT = ((DTA(5) * 256 + DTA(6)) * 256 + DTA(7)) * 256 + DTA(8)
   *
   PAD = "" ; N = LEN(SVAL)
   * Pad input string with 0x00 if not multiple of 8!
   LOOP UNTIL MOD(N, 8) = 0 DO
      PAD = PAD:CHAR(0)
      N = N + 1
   REPEAT
   IF PAD > "" THEN SVAL = SVAL:PAD
   *
   * Encrypt input string!
   *
   OUTSTR = ""
   FOR PTR = 1 TO N STEP 8
      VAL = (SEQ(SVAL[PTR, 1]) * 256 + SEQ(SVAL[PTR+1, 1])) * 256
      VAL = (VAL + SEQ(SVAL[PTR+2, 1])) * 256 + SEQ(SVAL[PTR+3, 1])
      VAL1 = LEFT
      GOSUB 400
      LEFT = VAL
      VAL = (SEQ(SVAL[PTR+4, 1]) * 256 + SEQ(SVAL[PTR+5, 1])) * 256
      VAL = (VAL + SEQ(SVAL[PTR+6, 1])) * 256 + SEQ(SVAL[PTR+7, 1])
      VAL1 = RIGHT
      GOSUB 400
      RIGHT = VAL
      GOSUB 200
      PAD = CHAR(INT(LEFT / P2TO24)):CHAR(MOD(INT(LEFT / P2TO16), P2TO8))
      PAD = PAD:CHAR(MOD(INT(LEFT / P2TO8), P2TO8)):CHAR(MOD(LEFT, P2TO8))
      PAD = PAD:CHAR(INT(RIGHT / P2TO24)):CHAR(MOD(INT(RIGHT / P2TO16), P2TO8))
      PAD = PAD:CHAR(MOD(INT(RIGHT / P2TO8), P2TO8)):CHAR(MOD(RIGHT, P2TO8))
      OUTSTR = OUTSTR:PAD
   NEXT PTR
   SVAL = OUTSTR
   OUTSTR = ""
   RETURN
   *
* *************************************************** *
* Decrypt a string passed in 'SVAL' using Blowfish in *
* CBC mode. We assume that the string was encrypted   *
* using the code in subroutine 500. IV data passed in *
* array 'DTA'.                                        *
* *************************************************** *
600*
   * Get inital left & right 32 bit values for IV
   IVL = ((DTA(1) * 256 + DTA(2)) * 256 + DTA(3)) * 256 + DTA(4)
   IVR = ((DTA(5) * 256 + DTA(6)) * 256 + DTA(7)) * 256 + DTA(8)
   *
   * Decrypt the input string!
   *
   OUTSTR = ""
   N = LEN(SVAL)
   FOR PTR = 1 TO N STEP 8
      LEFT  = (SEQ(SVAL[PTR, 1]) * 256 + SEQ(SVAL[PTR+1, 1])) * 256
      LEFT  = (LEFT + SEQ(SVAL[PTR+2, 1])) * 256 + SEQ(SVAL[PTR+3, 1])
      RIGHT = (SEQ(SVAL[PTR+4, 1]) * 256 + SEQ(SVAL[PTR+5, 1])) * 256
      RIGHT = (RIGHT + SEQ(SVAL[PTR+6, 1])) * 256 + SEQ(SVAL[PTR+7, 1])
      * Preserve current values of 'LEFT' and 'RIGHT'
      SAVE.LEFT  = LEFT
      SAVE.RIGHT = RIGHT
      * Pass block through Blowfish decryption
      GOSUB 300
      VAL = LEFT
      VAL1 = IVL
      GOSUB 400
      PAD = CHAR(INT(VAL / P2TO24)):CHAR(MOD(INT(VAL / P2TO16), P2TO8))
      PAD = PAD:CHAR(MOD(INT(VAL / P2TO8), P2TO8)):CHAR(MOD(VAL, P2TO8))
      VAL = RIGHT
      VAL1 = IVR
      GOSUB 400
      PAD = PAD:CHAR(INT(VAL / P2TO24)):CHAR(MOD(INT(VAL / P2TO16), P2TO8))
      PAD = PAD:CHAR(MOD(INT(VAL / P2TO8), P2TO8)):CHAR(MOD(VAL, P2TO8))
      OUTSTR = OUTSTR:PAD
      IVL = SAVE.LEFT
      IVR = SAVE.RIGHT
   NEXT PTR
   SVAL = OUTSTR
   OUTSTR = ""
   RETURN
   *
* ******************************************************* *
* Expands a user key into a Blowfish session key, and     *
* generates the session S-boxes. The key bytes are first  *
* extracted from the user key and then used, repeditively *
* if need be, to build the contents of the session key    *
* and S-box values. An error is generated if there are no *
* characters in the user key.                             *
* ******************************************************* *
900*
   PKEY(1) =608135816 ; PKEY(2) =2242054355; PKEY(3) =320440878 ; PKEY(4) =57701188
   PKEY(5) =2752067618; PKEY(6) =698298832 ; PKEY(7) =137296536 ; PKEY(8) =3964562569
   PKEY(9) =1160258022; PKEY(10)=953160567 ; PKEY(11)=3193202383; PKEY(12)=887688300
   PKEY(13)=3232508343; PKEY(14)=3380367581; PKEY(15)=1065670069; PKEY(16)=3041331479
   PKEY(17)=2450970073; PKEY(18)=2306472731
   *
   SKEY(1)   =3509652390; SKEY(2)   =2564797868; SKEY(3)   = 805139163; SKEY(4)   =3491422135
   SKEY(5)   =3101798381; SKEY(6)   =1780907670; SKEY(7)   =3128725573; SKEY(8)   =4046225305
   SKEY(9)   = 614570311; SKEY(10)  =3012652279; SKEY(11)  = 134345442; SKEY(12)  =2240740374
   SKEY(13)  =1667834072; SKEY(14)  =1901547113; SKEY(15)  =2757295779; SKEY(16)  =4103290238
   SKEY(17)  = 227898511; SKEY(18)  =1921955416; SKEY(19)  =1904987480; SKEY(20)  =2182433518
   SKEY(21)  =2069144605; SKEY(22)  =3260701109; SKEY(23)  =2620446009; SKEY(24)  = 720527379
   SKEY(25)  =3318853667; SKEY(26)  = 677414384; SKEY(27)  =3393288472; SKEY(28)  =3101374703
   SKEY(29)  =2390351024; SKEY(30)  =1614419982; SKEY(31)  =1822297739; SKEY(32)  =2954791486
   SKEY(33)  =3608508353; SKEY(34)  =3174124327; SKEY(35)  =2024746970; SKEY(36)  =1432378464
   SKEY(37)  =3864339955; SKEY(38)  =2857741204; SKEY(39)  =1464375394; SKEY(40)  =1676153920
   SKEY(41)  =1439316330; SKEY(42)  = 715854006; SKEY(43)  =3033291828; SKEY(44)  = 289532110
   SKEY(45)  =2706671279; SKEY(46)  =2087905683; SKEY(47)  =3018724369; SKEY(48)  =1668267050
   SKEY(49)  = 732546397; SKEY(50)  =1947742710; SKEY(51)  =3462151702; SKEY(52)  =2609353502
   SKEY(53)  =2950085171; SKEY(54)  =1814351708; SKEY(55)  =2050118529; SKEY(56)  = 680887927
   SKEY(57)  = 999245976; SKEY(58)  =1800124847; SKEY(59)  =3300911131; SKEY(60)  =1713906067
   SKEY(61)  =1641548236; SKEY(62)  =4213287313; SKEY(63)  =1216130144; SKEY(64)  =1575780402
   SKEY(65)  =4018429277; SKEY(66)  =3917837745; SKEY(67)  =3693486850; SKEY(68)  =3949271944
   SKEY(69)  = 596196993; SKEY(70)  =3549867205; SKEY(71)  = 258830323; SKEY(72)  =2213823033
   SKEY(73)  = 772490370; SKEY(74)  =2760122372; SKEY(75)  =1774776394; SKEY(76)  =2652871518
   SKEY(77)  = 566650946; SKEY(78)  =4142492826; SKEY(79)  =1728879713; SKEY(80)  =2882767088
   SKEY(81)  =1783734482; SKEY(82)  =3629395816; SKEY(83)  =2517608232; SKEY(84)  =2874225571
   SKEY(85)  =1861159788; SKEY(86)  = 326777828; SKEY(87)  =3124490320; SKEY(88)  =2130389656
   SKEY(89)  =2716951837; SKEY(90)  = 967770486; SKEY(91)  =1724537150; SKEY(92)  =2185432712
   SKEY(93)  =2364442137; SKEY(94)  =1164943284; SKEY(95)  =2105845187; SKEY(96)  = 998989502
   SKEY(97)  =3765401048; SKEY(98)  =2244026483; SKEY(99)  =1075463327; SKEY(100) =1455516326
   SKEY(101) =1322494562; SKEY(102) = 910128902; SKEY(103) = 469688178; SKEY(104) =1117454909
   SKEY(105) = 936433444; SKEY(106) =3490320968; SKEY(107) =3675253459; SKEY(108) =1240580251
   SKEY(109) = 122909385; SKEY(110) =2157517691; SKEY(111) = 634681816; SKEY(112) =4142456567
   SKEY(113) =3825094682; SKEY(114) =3061402683; SKEY(115) =2540495037; SKEY(116) =  79693498
   SKEY(117) =3249098678; SKEY(118) =1084186820; SKEY(119) =1583128258; SKEY(120) = 426386531
   SKEY(121) =1761308591; SKEY(122) =1047286709; SKEY(123) = 322548459; SKEY(124) = 995290223
   SKEY(125) =1845252383; SKEY(126) =2603652396; SKEY(127) =3431023940; SKEY(128) =2942221577
   SKEY(129) =3202600964; SKEY(130) =3727903485; SKEY(131) =1712269319; SKEY(132) = 422464435
   SKEY(133) =3234572375; SKEY(134) =1170764815; SKEY(135) =3523960633; SKEY(136) =3117677531
   SKEY(137) =1434042557; SKEY(138) = 442511882; SKEY(139) =3600875718; SKEY(140) =1076654713
   SKEY(141) =1738483198; SKEY(142) =4213154764; SKEY(143) =2393238008; SKEY(144) =3677496056
   SKEY(145) =1014306527; SKEY(146) =4251020053; SKEY(147) = 793779912; SKEY(148) =2902807211
   SKEY(149) = 842905082; SKEY(150) =4246964064; SKEY(151) =1395751752; SKEY(152) =1040244610
   SKEY(153) =2656851899; SKEY(154) =3396308128; SKEY(155) = 445077038; SKEY(156) =3742853595
   SKEY(157) =3577915638; SKEY(158) = 679411651; SKEY(159) =2892444358; SKEY(160) =2354009459
   SKEY(161) =1767581616; SKEY(162) =3150600392; SKEY(163) =3791627101; SKEY(164) =3102740896
   SKEY(165) = 284835224; SKEY(166) =4246832056; SKEY(167) =1258075500; SKEY(168) = 768725851
   SKEY(169) =2589189241; SKEY(170) =3069724005; SKEY(171) =3532540348; SKEY(172) =1274779536
   SKEY(173) =3789419226; SKEY(174) =2764799539; SKEY(175) =1660621633; SKEY(176) =3471099624
   SKEY(177) =4011903706; SKEY(178) = 913787905; SKEY(179) =3497959166; SKEY(180) = 737222580
   SKEY(181) =2514213453; SKEY(182) =2928710040; SKEY(183) =3937242737; SKEY(184) =1804850592
   SKEY(185) =3499020752; SKEY(186) =2949064160; SKEY(187) =2386320175; SKEY(188) =2390070455
   SKEY(189) =2415321851; SKEY(190) =4061277028; SKEY(191) =2290661394; SKEY(192) =2416832540
   SKEY(193) =1336762016; SKEY(194) =1754252060; SKEY(195) =3520065937; SKEY(196) =3014181293
   SKEY(197) = 791618072; SKEY(198) =3188594551; SKEY(199) =3933548030; SKEY(200) =2332172193
   SKEY(201) =3852520463; SKEY(202) =3043980520; SKEY(203) = 413987798; SKEY(204) =3465142937
   SKEY(205) =3030929376; SKEY(206) =4245938359; SKEY(207) =2093235073; SKEY(208) =3534596313
   SKEY(209) = 375366246; SKEY(210) =2157278981; SKEY(211) =2479649556; SKEY(212) = 555357303
   SKEY(213) =3870105701; SKEY(214) =2008414854; SKEY(215) =3344188149; SKEY(216) =4221384143
   SKEY(217) =3956125452; SKEY(218) =2067696032; SKEY(219) =3594591187; SKEY(220) =2921233993
   SKEY(221) =   2428461; SKEY(222) = 544322398; SKEY(223) = 577241275; SKEY(224) =1471733935
   SKEY(225) = 610547355; SKEY(226) =4027169054; SKEY(227) =1432588573; SKEY(228) =1507829418
   SKEY(229) =2025931657; SKEY(230) =3646575487; SKEY(231) = 545086370; SKEY(232) =  48609733
   SKEY(233) =2200306550; SKEY(234) =1653985193; SKEY(235) = 298326376; SKEY(236) =1316178497
   SKEY(237) =3007786442; SKEY(238) =2064951626; SKEY(239) = 458293330; SKEY(240) =2589141269
   SKEY(241) =3591329599; SKEY(242) =3164325604; SKEY(243) = 727753846; SKEY(244) =2179363840
   SKEY(245) = 146436021; SKEY(246) =1461446943; SKEY(247) =4069977195; SKEY(248) = 705550613
   SKEY(249) =3059967265; SKEY(250) =3887724982; SKEY(251) =4281599278; SKEY(252) =3313849956
   SKEY(253) =1404054877; SKEY(254) =2845806497; SKEY(255) = 146425753; SKEY(256) =1854211946
   SKEY(257) =1266315497; SKEY(258) =3048417604; SKEY(259) =3681880366; SKEY(260) =3289982499
   SKEY(261) =2909710000; SKEY(262) =1235738493; SKEY(263) =2632868024; SKEY(264) =2414719590
   SKEY(265) =3970600049; SKEY(266) =1771706367; SKEY(267) =1449415276; SKEY(268) =3266420449
   SKEY(269) = 422970021; SKEY(270) =1963543593; SKEY(271) =2690192192; SKEY(272) =3826793022
   SKEY(273) =1062508698; SKEY(274) =1531092325; SKEY(275) =1804592342; SKEY(276) =2583117782
   SKEY(277) =2714934279; SKEY(278) =4024971509; SKEY(279) =1294809318; SKEY(280) =4028980673
   SKEY(281) =1289560198; SKEY(282) =2221992742; SKEY(283) =1669523910; SKEY(284) =  35572830
   SKEY(285) = 157838143; SKEY(286) =1052438473; SKEY(287) =1016535060; SKEY(288) =1802137761
   SKEY(289) =1753167236; SKEY(290) =1386275462; SKEY(291) =3080475397; SKEY(292) =2857371447
   SKEY(293) =1040679964; SKEY(294) =2145300060; SKEY(295) =2390574316; SKEY(296) =1461121720
   SKEY(297) =2956646967; SKEY(298) =4031777805; SKEY(299) =4028374788; SKEY(300) =  33600511
   SKEY(301) =2920084762; SKEY(302) =1018524850; SKEY(303) = 629373528; SKEY(304) =3691585981
   SKEY(305) =3515945977; SKEY(306) =2091462646; SKEY(307) =2486323059; SKEY(308) = 586499841
   SKEY(309) = 988145025; SKEY(310) = 935516892; SKEY(311) =3367335476; SKEY(312) =2599673255
   SKEY(313) =2839830854; SKEY(314) = 265290510; SKEY(315) =3972581182; SKEY(316) =2759138881
   SKEY(317) =3795373465; SKEY(318) =1005194799; SKEY(319) = 847297441; SKEY(320) = 406762289
   SKEY(321) =1314163512; SKEY(322) =1332590856; SKEY(323) =1866599683; SKEY(324) =4127851711
   SKEY(325) = 750260880; SKEY(326) = 613907577; SKEY(327) =1450815602; SKEY(328) =3165620655
   SKEY(329) =3734664991; SKEY(330) =3650291728; SKEY(331) =3012275730; SKEY(332) =3704569646
   SKEY(333) =1427272223; SKEY(334) = 778793252; SKEY(335) =1343938022; SKEY(336) =2676280711
   SKEY(337) =2052605720; SKEY(338) =1946737175; SKEY(339) =3164576444; SKEY(340) =3914038668
   SKEY(341) =3967478842; SKEY(342) =3682934266; SKEY(343) =1661551462; SKEY(344) =3294938066
   SKEY(345) =4011595847; SKEY(346) = 840292616; SKEY(347) =3712170807; SKEY(348) = 616741398
   SKEY(349) = 312560963; SKEY(350) = 711312465; SKEY(351) =1351876610; SKEY(352) = 322626781
   SKEY(353) =1910503582; SKEY(354) = 271666773; SKEY(355) =2175563734; SKEY(356) =1594956187
   SKEY(357) =  70604529; SKEY(358) =3617834859; SKEY(359) =1007753275; SKEY(360) =1495573769
   SKEY(361) =4069517037; SKEY(362) =2549218298; SKEY(363) =2663038764; SKEY(364) = 504708206
   SKEY(365) =2263041392; SKEY(366) =3941167025; SKEY(367) =2249088522; SKEY(368) =1514023603
   SKEY(369) =1998579484; SKEY(370) =1312622330; SKEY(371) = 694541497; SKEY(372) =2582060303
   SKEY(373) =2151582166; SKEY(374) =1382467621; SKEY(375) = 776784248; SKEY(376) =2618340202
   SKEY(377) =3323268794; SKEY(378) =2497899128; SKEY(379) =2784771155; SKEY(380) = 503983604
   SKEY(381) =4076293799; SKEY(382) = 907881277; SKEY(383) = 423175695; SKEY(384) = 432175456
   SKEY(385) =1378068232; SKEY(386) =4145222326; SKEY(387) =3954048622; SKEY(388) =3938656102
   SKEY(389) =3820766613; SKEY(390) =2793130115; SKEY(391) =2977904593; SKEY(392) =  26017576
   SKEY(393) =3274890735; SKEY(394) =3194772133; SKEY(395) =1700274565; SKEY(396) =1756076034
   SKEY(397) =4006520079; SKEY(398) =3677328699; SKEY(399) = 720338349; SKEY(400) =1533947780
   SKEY(401) = 354530856; SKEY(402) = 688349552; SKEY(403) =3973924725; SKEY(404) =1637815568
   SKEY(405) = 332179504; SKEY(406) =3949051286; SKEY(407) =  53804574; SKEY(408) =2852348879
   SKEY(409) =3044236432; SKEY(410) =1282449977; SKEY(411) =3583942155; SKEY(412) =3416972820
   SKEY(413) =4006381244; SKEY(414) =1617046695; SKEY(415) =2628476075; SKEY(416) =3002303598
   SKEY(417) =1686838959; SKEY(418) = 431878346; SKEY(419) =2686675385; SKEY(420) =1700445008
   SKEY(421) =1080580658; SKEY(422) =1009431731; SKEY(423) = 832498133; SKEY(424) =3223435511
   SKEY(425) =2605976345; SKEY(426) =2271191193; SKEY(427) =2516031870; SKEY(428) =1648197032
   SKEY(429) =4164389018; SKEY(430) =2548247927; SKEY(431) = 300782431; SKEY(432) = 375919233
   SKEY(433) = 238389289; SKEY(434) =3353747414; SKEY(435) =2531188641; SKEY(436) =2019080857
   SKEY(437) =1475708069; SKEY(438) = 455242339; SKEY(439) =2609103871; SKEY(440) = 448939670
   SKEY(441) =3451063019; SKEY(442) =1395535956; SKEY(443) =2413381860; SKEY(444) =1841049896
   SKEY(445) =1491858159; SKEY(446) = 885456874; SKEY(447) =4264095073; SKEY(448) =4001119347
   SKEY(449) =1565136089; SKEY(450) =3898914787; SKEY(451) =1108368660; SKEY(452) = 540939232
   SKEY(453) =1173283510; SKEY(454) =2745871338; SKEY(455) =3681308437; SKEY(456) =4207628240
   SKEY(457) =3343053890; SKEY(458) =4016749493; SKEY(459) =1699691293; SKEY(460) =1103962373
   SKEY(461) =3625875870; SKEY(462) =2256883143; SKEY(463) =3830138730; SKEY(464) =1031889488
   SKEY(465) =3479347698; SKEY(466) =1535977030; SKEY(467) =4236805024; SKEY(468) =3251091107
   SKEY(469) =2132092099; SKEY(470) =1774941330; SKEY(471) =1199868427; SKEY(472) =1452454533
   SKEY(473) = 157007616; SKEY(474) =2904115357; SKEY(475) = 342012276; SKEY(476) = 595725824
   SKEY(477) =1480756522; SKEY(478) = 206960106; SKEY(479) = 497939518; SKEY(480) = 591360097
   SKEY(481) = 863170706; SKEY(482) =2375253569; SKEY(483) =3596610801; SKEY(484) =1814182875
   SKEY(485) =2094937945; SKEY(486) =3421402208; SKEY(487) =1082520231; SKEY(488) =3463918190
   SKEY(489) =2785509508; SKEY(490) = 435703966; SKEY(491) =3908032597; SKEY(492) =1641649973
   SKEY(493) =2842273706; SKEY(494) =3305899714; SKEY(495) =1510255612; SKEY(496) =2148256476
   SKEY(497) =2655287854; SKEY(498) =3276092548; SKEY(499) =4258621189; SKEY(500) = 236887753
   SKEY(501) =3681803219; SKEY(502) = 274041037; SKEY(503) =1734335097; SKEY(504) =3815195456
   SKEY(505) =3317970021; SKEY(506) =1899903192; SKEY(507) =1026095262; SKEY(508) =4050517792
   SKEY(509) = 356393447; SKEY(510) =2410691914; SKEY(511) =3873677099; SKEY(512) =3682840055
   SKEY(513) =3913112168; SKEY(514) =2491498743; SKEY(515) =4132185628; SKEY(516) =2489919796
   SKEY(517) =1091903735; SKEY(518) =1979897079; SKEY(519) =3170134830; SKEY(520) =3567386728
   SKEY(521) =3557303409; SKEY(522) = 857797738; SKEY(523) =1136121015; SKEY(524) =1342202287
   SKEY(525) = 507115054; SKEY(526) =2535736646; SKEY(527) = 337727348; SKEY(528) =3213592640
   SKEY(529) =1301675037; SKEY(530) =2528481711; SKEY(531) =1895095763; SKEY(532) =1721773893
   SKEY(533) =3216771564; SKEY(534) =  62756741; SKEY(535) =2142006736; SKEY(536) = 835421444
   SKEY(537) =2531993523; SKEY(538) =1442658625; SKEY(539) =3659876326; SKEY(540) =2882144922
   SKEY(541) = 676362277; SKEY(542) =1392781812; SKEY(543) = 170690266; SKEY(544) =3921047035
   SKEY(545) =1759253602; SKEY(546) =3611846912; SKEY(547) =1745797284; SKEY(548) = 664899054
   SKEY(549) =1329594018; SKEY(550) =3901205900; SKEY(551) =3045908486; SKEY(552) =2062866102
   SKEY(553) =2865634940; SKEY(554) =3543621612; SKEY(555) =3464012697; SKEY(556) =1080764994
   SKEY(557) = 553557557; SKEY(558) =3656615353; SKEY(559) =3996768171; SKEY(560) = 991055499
   SKEY(561) = 499776247; SKEY(562) =1265440854; SKEY(563) = 648242737; SKEY(564) =3940784050
   SKEY(565) = 980351604; SKEY(566) =3713745714; SKEY(567) =1749149687; SKEY(568) =3396870395
   SKEY(569) =4211799374; SKEY(570) =3640570775; SKEY(571) =1161844396; SKEY(572) =3125318951
   SKEY(573) =1431517754; SKEY(574) = 545492359; SKEY(575) =4268468663; SKEY(576) =3499529547
   SKEY(577) =1437099964; SKEY(578) =2702547544; SKEY(579) =3433638243; SKEY(580) =2581715763
   SKEY(581) =2787789398; SKEY(582) =1060185593; SKEY(583) =1593081372; SKEY(584) =2418618748
   SKEY(585) =4260947970; SKEY(586) =  69676912; SKEY(587) =2159744348; SKEY(588) =  86519011
   SKEY(589) =2512459080; SKEY(590) =3838209314; SKEY(591) =1220612927; SKEY(592) =3339683548
   SKEY(593) = 133810670; SKEY(594) =1090789135; SKEY(595) =1078426020; SKEY(596) =1569222167
   SKEY(597) = 845107691; SKEY(598) =3583754449; SKEY(599) =4072456591; SKEY(600) =1091646820
   SKEY(601) = 628848692; SKEY(602) =1613405280; SKEY(603) =3757631651; SKEY(604) = 526609435
   SKEY(605) = 236106946; SKEY(606) =  48312990; SKEY(607) =2942717905; SKEY(608) =3402727701
   SKEY(609) =1797494240; SKEY(610) = 859738849; SKEY(611) = 992217954; SKEY(612) =4005476642
   SKEY(613) =2243076622; SKEY(614) =3870952857; SKEY(615) =3732016268; SKEY(616) = 765654824
   SKEY(617) =3490871365; SKEY(618) =2511836413; SKEY(619) =1685915746; SKEY(620) =3888969200
   SKEY(621) =1414112111; SKEY(622) =2273134842; SKEY(623) =3281911079; SKEY(624) =4080962846
   SKEY(625) = 172450625; SKEY(626) =2569994100; SKEY(627) = 980381355; SKEY(628) =4109958455
   SKEY(629) =2819808352; SKEY(630) =2716589560; SKEY(631) =2568741196; SKEY(632) =3681446669
   SKEY(633) =3329971472; SKEY(634) =1835478071; SKEY(635) = 660984891; SKEY(636) =3704678404
   SKEY(637) =4045999559; SKEY(638) =3422617507; SKEY(639) =3040415634; SKEY(640) =1762651403
   SKEY(641) =1719377915; SKEY(642) =3470491036; SKEY(643) =2693910283; SKEY(644) =3642056355
   SKEY(645) =3138596744; SKEY(646) =1364962596; SKEY(647) =2073328063; SKEY(648) =1983633131
   SKEY(649) = 926494387; SKEY(650) =3423689081; SKEY(651) =2150032023; SKEY(652) =4096667949
   SKEY(653) =1749200295; SKEY(654) =3328846651; SKEY(655) = 309677260; SKEY(656) =2016342300
   SKEY(657) =1779581495; SKEY(658) =3079819751; SKEY(659) = 111262694; SKEY(660) =1274766160
   SKEY(661) = 443224088; SKEY(662) = 298511866; SKEY(663) =1025883608; SKEY(664) =3806446537
   SKEY(665) =1145181785; SKEY(666) = 168956806; SKEY(667) =3641502830; SKEY(668) =3584813610
   SKEY(669) =1689216846; SKEY(670) =3666258015; SKEY(671) =3200248200; SKEY(672) =1692713982
   SKEY(673) =2646376535; SKEY(674) =4042768518; SKEY(675) =1618508792; SKEY(676) =1610833997
   SKEY(677) =3523052358; SKEY(678) =4130873264; SKEY(679) =2001055236; SKEY(680) =3610705100
   SKEY(681) =2202168115; SKEY(682) =4028541809; SKEY(683) =2961195399; SKEY(684) =1006657119
   SKEY(685) =2006996926; SKEY(686) =3186142756; SKEY(687) =1430667929; SKEY(688) =3210227297
   SKEY(689) =1314452623; SKEY(690) =4074634658; SKEY(691) =4101304120; SKEY(692) =2273951170
   SKEY(693) =1399257539; SKEY(694) =3367210612; SKEY(695) =3027628629; SKEY(696) =1190975929
   SKEY(697) =2062231137; SKEY(698) =2333990788; SKEY(699) =2221543033; SKEY(700) =2438960610
   SKEY(701) =1181637006; SKEY(702) = 548689776; SKEY(703) =2362791313; SKEY(704) =3372408396
   SKEY(705) =3104550113; SKEY(706) =3145860560; SKEY(707) = 296247880; SKEY(708) =1970579870
   SKEY(709) =3078560182; SKEY(710) =3769228297; SKEY(711) =1714227617; SKEY(712) =3291629107
   SKEY(713) =3898220290; SKEY(714) = 166772364; SKEY(715) =1251581989; SKEY(716) = 493813264
   SKEY(717) = 448347421; SKEY(718) = 195405023; SKEY(719) =2709975567; SKEY(720) = 677966185
   SKEY(721) =3703036547; SKEY(722) =1463355134; SKEY(723) =2715995803; SKEY(724) =1338867538
   SKEY(725) =1343315457; SKEY(726) =2802222074; SKEY(727) =2684532164; SKEY(728) = 233230375
   SKEY(729) =2599980071; SKEY(730) =2000651841; SKEY(731) =3277868038; SKEY(732) =1638401717
   SKEY(733) =4028070440; SKEY(734) =3237316320; SKEY(735) =   6314154; SKEY(736) = 819756386
   SKEY(737) = 300326615; SKEY(738) = 590932579; SKEY(739) =1405279636; SKEY(740) =3267499572
   SKEY(741) =3150704214; SKEY(742) =2428286686; SKEY(743) =3959192993; SKEY(744) =3461946742
   SKEY(745) =1862657033; SKEY(746) =1266418056; SKEY(747) = 963775037; SKEY(748) =2089974820
   SKEY(749) =2263052895; SKEY(750) =1917689273; SKEY(751) = 448879540; SKEY(752) =3550394620
   SKEY(753) =3981727096; SKEY(754) = 150775221; SKEY(755) =3627908307; SKEY(756) =1303187396
   SKEY(757) = 508620638; SKEY(758) =2975983352; SKEY(759) =2726630617; SKEY(760) =1817252668
   SKEY(761) =1876281319; SKEY(762) =1457606340; SKEY(763) = 908771278; SKEY(764) =3720792119
   SKEY(765) =3617206836; SKEY(766) =2455994898; SKEY(767) =1729034894; SKEY(768) =1080033504
   SKEY(769) = 976866871; SKEY(770) =3556439503; SKEY(771) =2881648439; SKEY(772) =1522871579
   SKEY(773) =1555064734; SKEY(774) =1336096578; SKEY(775) =3548522304; SKEY(776) =2579274686
   SKEY(777) =3574697629; SKEY(778) =3205460757; SKEY(779) =3593280638; SKEY(780) =3338716283
   SKEY(781) =3079412587; SKEY(782) = 564236357; SKEY(783) =2993598910; SKEY(784) =1781952180
   SKEY(785) =1464380207; SKEY(786) =3163844217; SKEY(787) =3332601554; SKEY(788) =1699332808
   SKEY(789) =1393555694; SKEY(790) =1183702653; SKEY(791) =3581086237; SKEY(792) =1288719814
   SKEY(793) = 691649499; SKEY(794) =2847557200; SKEY(795) =2895455976; SKEY(796) =3193889540
   SKEY(797) =2717570544; SKEY(798) =1781354906; SKEY(799) =1676643554; SKEY(800) =2592534050
   SKEY(801) =3230253752; SKEY(802) =1126444790; SKEY(803) =2770207658; SKEY(804) =2633158820
   SKEY(805) =2210423226; SKEY(806) =2615765581; SKEY(807) =2414155088; SKEY(808) =3127139286
   SKEY(809) = 673620729; SKEY(810) =2805611233; SKEY(811) =1269405062; SKEY(812) =4015350505
   SKEY(813) =3341807571; SKEY(814) =4149409754; SKEY(815) =1057255273; SKEY(816) =2012875353
   SKEY(817) =2162469141; SKEY(818) =2276492801; SKEY(819) =2601117357; SKEY(820) = 993977747
   SKEY(821) =3918593370; SKEY(822) =2654263191; SKEY(823) = 753973209; SKEY(824) =  36408145
   SKEY(825) =2530585658; SKEY(826) =  25011837; SKEY(827) =3520020182; SKEY(828) =2088578344
   SKEY(829) = 530523599; SKEY(830) =2918365339; SKEY(831) =1524020338; SKEY(832) =1518925132
   SKEY(833) =3760827505; SKEY(834) =3759777254; SKEY(835) =1202760957; SKEY(836) =3985898139
   SKEY(837) =3906192525; SKEY(838) = 674977740; SKEY(839) =4174734889; SKEY(840) =2031300136
   SKEY(841) =2019492241; SKEY(842) =3983892565; SKEY(843) =4153806404; SKEY(844) =3822280332
   SKEY(845) = 352677332; SKEY(846) =2297720250; SKEY(847) =  60907813; SKEY(848) =  90501309
   SKEY(849) =3286998549; SKEY(850) =1016092578; SKEY(851) =2535922412; SKEY(852) =2839152426
   SKEY(853) = 457141659; SKEY(854) = 509813237; SKEY(855) =4120667899; SKEY(856) = 652014361
   SKEY(857) =1966332200; SKEY(858) =2975202805; SKEY(859) =  55981186; SKEY(860) =2327461051
   SKEY(861) = 676427537; SKEY(862) =3255491064; SKEY(863) =2882294119; SKEY(864) =3433927263
   SKEY(865) =1307055953; SKEY(866) = 942726286; SKEY(867) = 933058658; SKEY(868) =2468411793
   SKEY(869) =3933900994; SKEY(870) =4215176142; SKEY(871) =1361170020; SKEY(872) =2001714738
   SKEY(873) =2830558078; SKEY(874) =3274259782; SKEY(875) =1222529897; SKEY(876) =1679025792
   SKEY(877) =2729314320; SKEY(878) =3714953764; SKEY(879) =1770335741; SKEY(880) = 151462246
   SKEY(881) =3013232138; SKEY(882) =1682292957; SKEY(883) =1483529935; SKEY(884) = 471910574
   SKEY(885) =1539241949; SKEY(886) = 458788160; SKEY(887) =3436315007; SKEY(888) =1807016891
   SKEY(889) =3718408830; SKEY(890) = 978976581; SKEY(891) =1043663428; SKEY(892) =3165965781
   SKEY(893) =1927990952; SKEY(894) =4200891579; SKEY(895) =2372276910; SKEY(896) =3208408903
   SKEY(897) =3533431907; SKEY(898) =1412390302; SKEY(899) =2931980059; SKEY(900) =4132332400
   SKEY(901) =1947078029; SKEY(902) =3881505623; SKEY(903) =4168226417; SKEY(904) =2941484381
   SKEY(905) =1077988104; SKEY(906) =1320477388; SKEY(907) = 886195818; SKEY(908) =  18198404
   SKEY(909) =3786409000; SKEY(910) =2509781533; SKEY(911) = 112762804; SKEY(912) =3463356488
   SKEY(913) =1866414978; SKEY(914) = 891333506; SKEY(915) =  18488651; SKEY(916) = 661792760
   SKEY(917) =1628790961; SKEY(918) =3885187036; SKEY(919) =3141171499; SKEY(920) = 876946877
   SKEY(921) =2693282273; SKEY(922) =1372485963; SKEY(923) = 791857591; SKEY(924) =2686433993
   SKEY(925) =3759982718; SKEY(926) =3167212022; SKEY(927) =3472953795; SKEY(928) =2716379847
   SKEY(929) = 445679433; SKEY(930) =3561995674; SKEY(931) =3504004811; SKEY(932) =3574258232
   SKEY(933) =  54117162; SKEY(934) =3331405415; SKEY(935) =2381918588; SKEY(936) =3769707343
   SKEY(937) =4154350007; SKEY(938) =1140177722; SKEY(939) =4074052095; SKEY(940) = 668550556
   SKEY(941) =3214352940; SKEY(942) = 367459370; SKEY(943) = 261225585; SKEY(944) =2610173221
   SKEY(945) =4209349473; SKEY(946) =3468074219; SKEY(947) =3265815641; SKEY(948) = 314222801
   SKEY(949) =3066103646; SKEY(950) =3808782860; SKEY(951) = 282218597; SKEY(952) =3406013506
   SKEY(953) =3773591054; SKEY(954) = 379116347; SKEY(955) =1285071038; SKEY(956) = 846784868
   SKEY(957) =2669647154; SKEY(958) =3771962079; SKEY(959) =3550491691; SKEY(960) =2305946142
   SKEY(961) = 453669953; SKEY(962) =1268987020; SKEY(963) =3317592352; SKEY(964) =3279303384
   SKEY(965) =3744833421; SKEY(966) =2610507566; SKEY(967) =3859509063; SKEY(968) = 266596637
   SKEY(969) =3847019092; SKEY(970) = 517658769; SKEY(971) =3462560207; SKEY(972) =3443424879
   SKEY(973) = 370717030; SKEY(974) =4247526661; SKEY(975) =2224018117; SKEY(976) =4143653529
   SKEY(977) =4112773975; SKEY(978) =2788324899; SKEY(979) =2477274417; SKEY(980) =1456262402
   SKEY(981) =2901442914; SKEY(982) =1517677493; SKEY(983) =1846949527; SKEY(984) =2295493580
   SKEY(985) =3734397586; SKEY(986) =2176403920; SKEY(987) =1280348187; SKEY(988) =1908823572
   SKEY(989) =3871786941; SKEY(990) = 846861322; SKEY(991) =1172426758; SKEY(992) =3287448474
   SKEY(993) =3383383037; SKEY(994) =1655181056; SKEY(995) =3139813346; SKEY(996) = 901632758
   SKEY(997) =1897031941; SKEY(998) =2986607138; SKEY(999) =3066810236; SKEY(1000)=3447102507
   SKEY(1001)=1393639104; SKEY(1002)= 373351379; SKEY(1003)= 950779232; SKEY(1004)= 625454576
   SKEY(1005)=3124240540; SKEY(1006)=4148612726; SKEY(1007)=2007998917; SKEY(1008)= 544563296
   SKEY(1009)=2244738638; SKEY(1010)=2330496472; SKEY(1011)=2058025392; SKEY(1012)=1291430526
   SKEY(1013)= 424198748; SKEY(1014)=  50039436; SKEY(1015)=  29584100; SKEY(1016)=3605783033
   SKEY(1017)=2429876329; SKEY(1018)=2791104160; SKEY(1019)=1057563949; SKEY(1020)=3255363231
   SKEY(1021)=3075367218; SKEY(1022)=3463963227; SKEY(1023)=1469046755; SKEY(1024)= 985887462
   *
   * We expect the key source to be up to MAX$KEY$LEN chars long, and at least
   * MIN$KEY$LEN chars in length.
   *
   J = LEN(SVAL)
   IF J < MIN$KEY$LEN   THEN
      * Error - User key too short!
      ERR = INVALID$KEY
      RETURN
   END ELSE
      IF J > MAX$KEY$LEN THEN
         * Truncate user key to too long!
         J = MAX$KEY$LEN
      END
   END
   *
   * Initialise session key array!
   *
   L = 1
   FOR I = 1 TO ROUNDS + 2
      VAL1 = 0
      FOR K = 1 TO 4
         VAL1 = VAL1 * 256 + SEQ(SVAL[L, 1])
         L = L + 1
         IF L > J THEN L = 1
      NEXT K
      VAL = PKEY(I)
      GOSUB 400
      PKEY(I) = VAL
   NEXT I
   *
   * Generate the session key!
   *
   LEFT  = 0
   RIGHT = 0
   FOR I = 1 TO ROUNDS + 2 STEP 2
      GOSUB 200
      PKEY(I)     = LEFT
      PKEY(I + 1) = RIGHT
   NEXT I
   *
   * Generate the session S-boxes
   *
   FOR I = 1 TO 1024 STEP 2
      GOSUB 200
      SKEY(I)     = LEFT
      SKEY(I + 1) = RIGHT
   NEXT I
   RETURN
*
   END