clr __zero_reg__
ret
+; a[i][j] = b[i][j] ^ ((~(b[i][(j + 1) % 5])) & (b[i][(j + 2) % 5]));
-.global keccak_theta
-keccak_theta:
- push_range 2, 8
+/*********************************************
+ * chi_step
+ *********************************************
+ input:
+ Y = a; uint8t *a;
+ X = b; uint8t *b;
+ Z = c; uint8t *c;
+ output:
+ a[0..7] ^= ~b[0..7] & c[0..7]
+ X += 8
+ Y += 8
+ Z += 8
+ r16 = 0
+ trash r21, r22, r23
+*/
+chi_step:
+ ldi r16, 8
+10:
+ ld r21, Y
+ ld r22, X+
+ ld r23, Z+
+ com r22
+ and r22, r23
+ eor r21, r22
+ st Y+, r21
+ dec r16
+ brne 10b
+ ret
+
+.global keccak_f1600
+keccak_f1600:
+ push_range 2, 9
push r16
push_range 28, 29
+ stack_alloc_large 200, r26, r27
+ adiw XL, 1
+
+ clr r9
+5:
movw r30, r24 ; Z = a
- movw r26, r22 ; X = b
- push_range 22, 25
ldi r19, 5
10:
ldi r16, 25
mov r8, r16
- pop YH
- pop YL
- pop B_REG_H
- pop B_REG_L
+ sbiw r24, 5 * 8 + 1
+ movw YL, r24
+ sbiw XL, 8
+ movw B_REG_L, XL
10:
ld r18, Y+
dec r8
brne 10b
+/*
+ -- chi --
+ for(i = 0; i < 5; ++i){
+ a[i][0] ^= ((~(b[i][1])) & (b[i][2]));
+ a[i][1] ^= ((~(b[i][2])) & (b[i][3]));
+ a[i][2] ^= ((~(b[i][3])) & (b[i][4]));
+ a[i][3] ^= ((~(b[i][4])) & (b[i][0]));
+ a[i][4] ^= ((~(b[i][0])) & (b[i][1]));
+
+ }
+*/
+ ; memcpy(a, b, 200)
+ ; X points at b + 32 + 8 = b + 40 = b[1][0] has to point to b[0][0]
+ ldi r16, 200
+ sbiw XL, 5 * 8
+ movw ZL, XL
+ subi YL, lo8(5 * 5 * 8)
+ sbci YH, hi8(5 * 5 * 8)
+ movw r2, YL
+10:
+ ld r22, X+
+ st Y+, r22
+ dec r16
+ brne 10b
+
+ ; Z points at b
+ movw XL, ZL
+ movw r4, ZL
+ adiw XL, 8
+ adiw ZL, 16
+ movw YL, r2
+ ldi r18, 5
+10:
+ rcall chi_step
+ rcall chi_step
+ rcall chi_step
+ sbiw ZL, 5 * 8
+ rcall chi_step
+ sbiw XL, 5 * 8
+ rcall chi_step
+ adiw XL, 5 * 8
+ adiw ZL, 5 * 8
+ dec r18
+ brne 10b
+
+ /* -- iota -- */
+ ldi r30, lo8(keccak_rc_comp)
+ ldi r31, hi8(keccak_rc_comp)
+ add r30, r9
+ adc r31, __zero_reg__
+ lpm r20, Z+
+ movw YL, r2
+ ldi r21, 0x80
+ bst r20, 6
+ brtc 10f
+ ldd r22, Y+7
+ eor r22, r21
+ std Y+7, r22
+10:
+ bst r20, 5
+ brtc 10f
+ ldd r22, Y+3
+ eor r22, r21
+ std Y+3, r22
+10:
+ bst r20, 4
+ brtc 10f
+ ldd r22, Y+1
+ eor r22, r21
+ std Y+1, r22
+10:
+ andi r20, 0x8f
+ ld r22, Y
+ eor r22, r20
+ st Y, r22
+
+ inc r9
+ mov r16, r9
+ cpi r16, 24
+ breq 20f
+ movw r24, YL
+ movw r26, r4
+ rjmp 5b
+20:
+
+ stack_free_large3 200
pop_range 28, 29
pop r16
- pop_range 2, 8
+ pop_range 2, 9
ret