initial checkin
This commit is contained in:
Karkat
284
crypto.asm
Normal file
284
crypto.asm
Normal file
@@ -0,0 +1,284 @@
|
||||
; $7F50D0 - $7F50FF - Block Cypher Parameters
|
||||
; $7F5100 - $7F51FF - Block Cypher Buffer
|
||||
!v = "$7F5100"
|
||||
!n = "$04"
|
||||
!MXResult = "$06"
|
||||
!dpScratch = "$08"
|
||||
!keyBase = "$7F50D0"
|
||||
|
||||
|
||||
!y = "$7F50E0"
|
||||
!z = "$7F50E4"
|
||||
!sum = "$7F50E8"
|
||||
|
||||
!p = "$7F50EC"
|
||||
!rounds = "$05"
|
||||
!e = "$7F50F0"
|
||||
|
||||
!upperScratch = "$7F50F2"
|
||||
|
||||
CryptoDelta:
|
||||
dl #$9e3779b9
|
||||
|
||||
macro LSR32(value,k)
|
||||
LDX.w <k>
|
||||
|
||||
?loop:
|
||||
LDA <value>+2
|
||||
LSR : STA <value>+2 ; do top part
|
||||
PHP ; push carry
|
||||
LDA <value>
|
||||
LSR ; do bottom part
|
||||
PLP ; pull carry
|
||||
BCC ?nc
|
||||
ORA #$80 ; pull in carry
|
||||
?nc:
|
||||
STA <value>
|
||||
|
||||
DEX
|
||||
CPX.w #$0000 : BNE ?loop
|
||||
endmacro
|
||||
|
||||
macro ASL32(value,k)
|
||||
LDX.w <k>
|
||||
|
||||
?loop:
|
||||
LDA <value>
|
||||
LSR : STA <value> ; do bottom part
|
||||
PHP ; push carry
|
||||
LDA <value>+2
|
||||
LSR
|
||||
PLP ; pull carry
|
||||
ADC.w #$0000
|
||||
STA <value>+2 ; do top part
|
||||
|
||||
DEX
|
||||
CPX.w #$0000 : BNE ?loop
|
||||
endmacro
|
||||
|
||||
CryptoMX:
|
||||
PHX
|
||||
LDA !z : STA !dpScratch
|
||||
LDA !z+2 : STA !dpScratch+2
|
||||
%LSR32(!dpScratch,#$05)
|
||||
|
||||
LDA !y : STA !dpScratch+4
|
||||
LDA !y+2 : STA !dpScratch+6
|
||||
%ASL32(!dpScratch+4,#$02)
|
||||
|
||||
LDA !dpScratch : EOR !dpScratch+4 : STA !upperScratch
|
||||
LDA !dpScratch+2 : EOR !dpScratch+6 : STA !upperScratch+2
|
||||
|
||||
;================================
|
||||
|
||||
LDA !z : STA !dpScratch
|
||||
LDA !z+2 : STA !dpScratch+2
|
||||
%ASL32(!dpScratch,#$04)
|
||||
|
||||
LDA !y : STA !dpScratch+4
|
||||
LDA !y+2 : STA !dpScratch+6
|
||||
%LSR32(!dpScratch,#$03)
|
||||
|
||||
LDA !dpScratch : EOR !dpScratch+4 : STA !upperScratch+4
|
||||
LDA !dpScratch+2 : EOR !dpScratch+6 : STA !upperScratch+6
|
||||
|
||||
;================================
|
||||
|
||||
LDA !upperScratch : !ADD !upperScratch+4 : STA !upperScratch
|
||||
LDA !upperScratch+2 : ADC !upperScratch+6 : STA !upperScratch+2
|
||||
|
||||
;================================
|
||||
|
||||
LDA !sum : EOR !y : STA !dpScratch
|
||||
LDA !sum+2 : EOR !y+2 : STA !dpScratch+2
|
||||
|
||||
;================================
|
||||
|
||||
LDA !p : AND.w #$0003 : EOR !e : ASL #2 : TAX ; put (p&3)^e into X
|
||||
LDA !keyBase, X : EOR !z : STA !upperScratch+4
|
||||
LDA !keyBase+2, X : EOR !z+2 : STA !upperScratch+6
|
||||
|
||||
;================================
|
||||
|
||||
LDA !upperScratch : EOR !upperScratch+4 : STA !MXResult
|
||||
LDA !upperScratch+2 : EOR !upperScratch+6 : STA !MXResult+2
|
||||
PLX
|
||||
RTS
|
||||
|
||||
!DIVIDEND_LOW = $4204
|
||||
!DIVIDEND_HIGH = $4205
|
||||
!DIVISOR = $4206
|
||||
!QUOTIENT_LOW = $4214
|
||||
!QUOTIENT_HIGH = $4215
|
||||
|
||||
XXTEA_Decode:
|
||||
PHP
|
||||
SEP #$20 ; set 8-bit accumulator
|
||||
|
||||
; rounds = 6 + 52/n;
|
||||
LDA.b #52 : STA !DIVIDEND_LOW ; decimal 52
|
||||
STZ !DIVIDEND_HIGH
|
||||
LDA !n : STA !DIVISOR
|
||||
; NOP #8 ; do something useful here?
|
||||
LDA.b #$06
|
||||
NOP #6
|
||||
!ADD !QUOTIENT_LOW
|
||||
STA !rounds
|
||||
|
||||
; sum = rounds*DELTA;
|
||||
LDA CryptoDelta : STA !dpScratch
|
||||
LDA CryptoDelta+1 : STA !dpScratch+1
|
||||
LDA CryptoDelta+2 : STA !dpScratch+2
|
||||
LDA CryptoDelta+3 : STA !dpScratch+3
|
||||
JSR .multiply
|
||||
LDA !dpScratch
|
||||
STA !sum
|
||||
|
||||
; y = v[0];
|
||||
REP #$20 ; set 16-bit accumulator
|
||||
LDA !v : STA !y
|
||||
LDA !v+2 : STA !y+2
|
||||
---
|
||||
LDA !sum : LSR #2 : AND #$03 : STA !e ; e = (sum >> 2) & 3;
|
||||
|
||||
LDA !n : !SUB #$01 : STA !p ; for (p=n-1; p>0; p--) {
|
||||
--
|
||||
; z = v[p-1];
|
||||
DEC : ASL #2 : TAX
|
||||
LDA !v, X : STA !z
|
||||
LDA !v+2, X : STA !z+2
|
||||
|
||||
; y = v[p] -= MX;
|
||||
JSR CryptoMX
|
||||
LDA !p : ASL #2 : TAX
|
||||
LDA !v, X : !SUB !MXResult : STA !v, X : STA !y
|
||||
LDA !v+2, X : SBC !MXResult+2 : STA !v+2, X : STA !y+2
|
||||
|
||||
LDA !p : DEC : STA !p : BNE -- ; }
|
||||
|
||||
; z = v[n-1];
|
||||
LDA !n : DEC : ASL #2 : TAX
|
||||
LDA !v, X : STA !z
|
||||
LDA !v+2, X : STA !z+2
|
||||
|
||||
; y = v[0] -= MX;
|
||||
JSR CryptoMX
|
||||
LDA !v : !SUB !MXResult : STA !v : STA !y
|
||||
LDA !v+2 : SBC !MXResult+2 : STA !v+2 : STA !y+2
|
||||
|
||||
; sum -= DELTA;
|
||||
LDA !sum : !SUB CryptoDelta : STA !sum
|
||||
LDA !sum+2 : !SUB CryptoDelta+2 : STA !sum+2
|
||||
|
||||
LDA !rounds : BEQ + : BRL --- : + ; } while (--rounds);
|
||||
PLP
|
||||
RTL
|
||||
|
||||
;void btea(uint32_t *v, int n, uint32_t const key[4]) {
|
||||
; uint32_t y, z, sum;
|
||||
; unsigned p, rounds, e;
|
||||
|
||||
; } else if (n < -1) { /* Decoding Part */
|
||||
; n = -n;
|
||||
; rounds = 6 + 52/n;
|
||||
; sum = rounds*DELTA;
|
||||
; y = v[0];
|
||||
; do {
|
||||
; e = (sum >> 2) & 3;
|
||||
; for (p=n-1; p>0; p--) {
|
||||
; z = v[p-1];
|
||||
; y = v[p] -= MX;
|
||||
; }
|
||||
; z = v[n-1];
|
||||
; y = v[0] -= MX;
|
||||
; sum -= DELTA;
|
||||
; } while (--rounds);
|
||||
; }
|
||||
|
||||
.multiply
|
||||
LDA #$00
|
||||
STA !upperScratch+4 ;Clear upper half of
|
||||
STA !upperScratch+5 ;!upperScratchuct
|
||||
STA !upperScratch+6
|
||||
STA !upperScratch+7
|
||||
LDX #$20 ;Set binary count to 32
|
||||
.shift_r
|
||||
LSR !dpScratch+3 ;Shift multiplyer right
|
||||
ROR !dpScratch+2
|
||||
ROR !dpScratch+1
|
||||
ROR !dpScratch
|
||||
BCC .rotate_r ;Go rotate right if c = 0
|
||||
LDA !upperScratch+4 ;Get upper half of !upperScratchuct
|
||||
!ADD !rounds ; and add multiplicand to it
|
||||
STA !upperScratch+4
|
||||
LDA !upperScratch+5
|
||||
ADC.w #$00
|
||||
STA !upperScratch+5
|
||||
LDA !upperScratch+6
|
||||
ADC.w #$00
|
||||
STA !upperScratch+6
|
||||
LDA !upperScratch+7
|
||||
ADC.w #$00
|
||||
.rotate_r
|
||||
ROR a ;Rotate partial !upperScratchuct
|
||||
STA !upperScratch+7 ; right
|
||||
ROR !upperScratch+6
|
||||
ROR !upperScratch+5
|
||||
ROR !upperScratch+4
|
||||
ROR !upperScratch+3
|
||||
ROR !upperScratch+2
|
||||
ROR !upperScratch+1
|
||||
ROR !upperScratch
|
||||
DEX ;Decrement bit count and
|
||||
BNE .shift_r ; loop until 32 bits are done
|
||||
;LDA MULXP1 ;Add dps and put sum in MULXP2
|
||||
;!ADD MULXP2
|
||||
;STA MULXP2
|
||||
RTS
|
||||
|
||||
;BTEA will encode or decode n words as a single block where n > 1
|
||||
;
|
||||
;v is the n word data vector
|
||||
;k is the 4 word key
|
||||
;n is negative for decoding
|
||||
;if n is zero result is 1 and no coding or decoding takes place, otherwise the result is zero
|
||||
;assumes 32 bit 'long' and same endian coding and decoding
|
||||
;#include <stdint.h>
|
||||
;#define DELTA 0x9e3779b9
|
||||
;#define MX (((z>>5^y<<2) + (y>>3^z<<4)) ^ ((sum^y) + (key[(p&3)^e] ^ z)))
|
||||
;#define MX ((((z>>5)^(y<<2)) + ((y>>3)^(z<<4))) ^ ((sum^y) + (key[(p&3)^e] ^ z)))
|
||||
;
|
||||
;void btea(uint32_t *v, int n, uint32_t const key[4]) {
|
||||
; uint32_t y, z, sum;
|
||||
; unsigned p, rounds, e;
|
||||
; if (n > 1) { /* Coding Part */
|
||||
; rounds = 6 + 52/n;
|
||||
; sum = 0;
|
||||
; z = v[n-1];
|
||||
; do {
|
||||
; sum += DELTA;
|
||||
; e = (sum >> 2) & 3;
|
||||
; for (p=0; p<n-1; p++) {
|
||||
; y = v[p+1];
|
||||
; z = v[p] += MX;
|
||||
; }
|
||||
; y = v[0];
|
||||
; z = v[n-1] += MX;
|
||||
; } while (--rounds);
|
||||
; } else if (n < -1) { /* Decoding Part */
|
||||
; n = -n;
|
||||
; rounds = 6 + 52/n;
|
||||
; sum = rounds*DELTA;
|
||||
; y = v[0];
|
||||
; do {
|
||||
; e = (sum >> 2) & 3;
|
||||
; for (p=n-1; p>0; p--) {
|
||||
; z = v[p-1];
|
||||
; y = v[p] -= MX;
|
||||
; }
|
||||
; z = v[n-1];
|
||||
; y = v[0] -= MX;
|
||||
; sum -= DELTA;
|
||||
; } while (--rounds);
|
||||
; }
|
||||
;}
|
||||
Reference in New Issue
Block a user