+++ /dev/null
-/* sha256-asm.S */
-/*
- This file is part of the AVR-Crypto-Lib.
- Copyright (C) 2008 Daniel Otte (daniel.otte@rub.de)
-
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-/*
- * Author: Daniel Otte
- *
- * License: GPLv3 or later
-*/
-; sha-256 implementation in assembler
-SHA256_BLOCK_BITS = 512
-SHA256_HASH_BITS = 256
-
-.macro precall
- /* push r18 - r27, r30 - r31*/
- push r0
- push r1
- push r18
- push r19
- push r20
- push r21
- push r22
- push r23
- push r24
- push r25
- push r26
- push r27
- push r30
- push r31
- clr r1
-.endm
-
-.macro postcall
- pop r31
- pop r30
- pop r27
- pop r26
- pop r25
- pop r24
- pop r23
- pop r22
- pop r21
- pop r20
- pop r19
- pop r18
- pop r1
- pop r0
-.endm
-
-
-.macro hexdump length
- push r27
- push r26
- ldi r25, '\r'
- mov r24, r25
- call uart_putc
- ldi r25, '\n'
- mov r24, r25
- call uart_putc
- pop r26
- pop r27
- movw r24, r26
-.if \length > 16
- ldi r22, lo8(16)
- ldi r23, hi8(16)
- push r27
- push r26
- call uart_hexdump
- pop r26
- pop r27
- adiw r26, 16
- hexdump \length-16
-.else
- ldi r22, lo8(\length)
- ldi r23, hi8(\length)
- call uart_hexdump
-.endif
-.endm
-
-/* X points to Block */
-.macro dbg_hexdump length
- precall
- hexdump \length
- postcall
-.endm
-
-.section .text
-
-SPL = 0x3D
-SPH = 0x3E
-SREG = 0x3F
-
-
-;
-;sha256_ctx_t is:
-;
-; [h0][h1][h2][h3][h4][h5][h6][h7][length]
-; hn is 32 bit large, length is 64 bit large
-
-;###########################################################
-
-.global sha256_ctx2hash
-; === sha256_ctx2hash ===
-; this function converts a state into a normal hash (bytestring)
-; param1: the 16-bit destination pointer
-; given in r25,r24 (r25 is most significant)
-; param2: the 16-bit pointer to sha256_ctx structure
-; given in r23,r22
-sha256_ctx2hash:
- movw r26, r22
- movw r30, r24
- ldi r21, 8
- sbiw r26, 4
-1:
- ldi r20, 4
- adiw r26, 8
-2:
- ld r0, -X
- st Z+, r0
- dec r20
- brne 2b
-
- dec r21
- brne 1b
-
- ret
-
-;###########################################################
-
-.global sha256
-; === sha256 ===
-; this function calculates SHA-256 hashes from messages in RAM
-; param1: the 16-bit hash destination pointer
-; given in r25,r24 (r25 is most significant)
-; param2: the 16-bit pointer to message
-; given in r23,r22
-; param3: 32-bit length value (length of message in bits)
-; given in r21,r20,r19,r18
-sha256:
-sha256_prolog:
- push r8
- push r9
- push r10
- push r11
- push r12
- push r13
- push r16
- push r17
- in r16, SPL
- in r17, SPH
- subi r16, 8*4+8
- sbci r17, 0
- in r0, SREG
- cli
- out SPL, r16
- out SPH, r17
- out SREG, r0
-
- push r25
- push r24
- inc r16
- adc r17, r1
-
- movw r8, r18 /* backup of length*/
- movw r10, r20
-
- movw r12, r22 /* backup pf msg-ptr */
-
- movw r24, r16
- rcall sha256_init
- /* if length >= 512 */
-1:
- tst r11
- brne 4f
- tst r10
- brne 4f
- mov r19, r9
- cpi r19, 0x02
- brlo 4f
-
- movw r24, r16
- movw r22, r12
- rcall sha256_nextBlock
- ldi r19, 0x64
- add r22, r19
- adc r23, r1
- /* length -= 512 */
- ldi r19, 0x02
- sub r9, r19
- sbc r10, r1
- sbc r11, r1
- rjmp 1b
-
-4:
- movw r24, r16
- movw r22, r12
- movw r20, r8
- rcall sha256_lastBlock
-
- pop r24
- pop r25
- movw r22, r16
- rcall sha256_ctx2hash
-
-sha256_epilog:
- in r30, SPL
- in r31, SPH
- adiw r30, 8*4+8
- in r0, SREG
- cli
- out SPL, r30
- out SPH, r31
- out SREG, r0
- pop r17
- pop r16
- pop r13
- pop r12
- pop r11
- pop r10
- pop r9
- pop r8
- ret
-
-;###########################################################
-
-
-; block MUST NOT be larger than 64 bytes
-
-.global sha256_lastBlock
-; === sha256_lastBlock ===
-; this function does padding & Co. for calculating SHA-256 hashes
-; param1: the 16-bit pointer to sha256_ctx structure
-; given in r25,r24 (r25 is most significant)
-; param2: an 16-bit pointer to 64 byte block to hash
-; given in r23,r22
-; param3: an 16-bit integer specifing length of block in bits
-; given in r21,r20
-sha256_lastBlock_localSpace = (SHA256_BLOCK_BITS/8+1)
-
-
-sha256_lastBlock:
- cpi r21, 0x02
- brlo sha256_lastBlock_prolog
- push r25
- push r24
- push r23
- push r22
- push r21
- push r20
- rcall sha256_nextBlock
- pop r20
- pop r21
- pop r22
- pop r23
- pop r24
- pop r25
- subi r21, 0x02
- subi r23, -2
- rjmp sha256_lastBlock
-sha256_lastBlock_prolog:
- /* allocate space on stack */
- in r30, SPL
- in r31, SPH
- in r1, SREG
- subi r30, lo8(64)
- sbci r31, hi8(64)
- cli
- out SPL, r30
- out SPH, r31
- out SREG,r1
-
- adiw r30, 1 /* SP points to next free byte on stack */
- mov r18, r20 /* r20 = LSB(length) */
- lsr r18
- lsr r18
- lsr r18
- bst r21, 0 /* may be we should explain this ... */
- bld r18, 5 /* now: r18 == length/8 (aka. length in bytes) */
-
-
- movw r26, r22 /* X points to begin of msg */
- tst r18
- breq sha256_lastBlock_post_copy
- mov r1, r18
-sha256_lastBlock_copy_loop:
- ld r0, X+
- st Z+, r0
- dec r1
- brne sha256_lastBlock_copy_loop
-sha256_lastBlock_post_copy:
-sha256_lastBlock_insert_stuffing_bit:
- ldi r19, 0x80
- mov r0,r19
- ldi r19, 0x07
- and r19, r20 /* if we are in bitmode */
- breq 2f /* no bitmode */
-1:
- lsr r0
- dec r19
- brne 1b
- ld r19, X
-/* maybe we should do some ANDing here, just for safety */
- or r0, r19
-2:
- st Z+, r0
- inc r18
-
-/* checking stuff here */
- cpi r18, 64-8+1
- brsh 0f
- rjmp sha256_lastBlock_insert_zeros
-0:
- /* oh shit, we landed here */
- /* first we have to fill it up with zeros */
- ldi r19, 64
- sub r19, r18
- breq 2f
-1:
- st Z+, r1
- dec r19
- brne 1b
-2:
- sbiw r30, 63
- sbiw r30, 1
- movw r22, r30
-
- push r31
- push r30
- push r25
- push r24
- push r21
- push r20
- rcall sha256_nextBlock
- pop r20
- pop r21
- pop r24
- pop r25
- pop r30
- pop r31
-
- /* now we should subtract 512 from length */
- movw r26, r24
- adiw r26, 4*8+1 /* we can skip the lowest byte */
- ld r19, X
- subi r19, hi8(512)
- st X+, r19
- ldi r18, 6
-1:
- ld r19, X
- sbci r19, 0
- st X+, r19
- dec r18
- brne 1b
-
-; clr r18 /* not neccessary ;-) */
- /* reset Z pointer to begin of block */
-
-sha256_lastBlock_insert_zeros:
- ldi r19, 64-8
- sub r19, r18
- breq sha256_lastBlock_insert_length
- clr r1
-1:
- st Z+, r1 /* r1 is still zero */
- dec r19
- brne 1b
-
-; rjmp sha256_lastBlock_epilog
-sha256_lastBlock_insert_length:
- movw r26, r24 /* X points to state */
- adiw r26, 8*4 /* X points to (state.length) */
- adiw r30, 8 /* Z points one after the last byte of block */
- ld r0, X+
- add r0, r20
- st -Z, r0
- ld r0, X+
- adc r0, r21
- st -Z, r0
- ldi r19, 6
-1:
- ld r0, X+
- adc r0, r1
- st -Z, r0
- dec r19
- brne 1b
-
- sbiw r30, 64-8
- movw r22, r30
- rcall sha256_nextBlock
-
-sha256_lastBlock_epilog:
- in r30, SPL
- in r31, SPH
- in r1, SREG
- adiw r30, 63 ; lo8(64)
- adiw r30, 1 ; hi8(64)
- cli
- out SPL, r30
- out SPH, r31
- out SREG,r1
- clr r1
- clr r0
- ret
-
-/**/
-;###########################################################
-
-.global sha256_nextBlock
-; === sha256_nextBlock ===
-; this is the core function for calculating SHA-256 hashes
-; param1: the 16-bit pointer to sha256_ctx structure
-; given in r25,r24 (r25 is most significant)
-; param2: an 16-bit pointer to 64 byte block to hash
-; given in r23,r22
-sha256_nextBlock_localSpace = (64+8)*4 ; 64 32-bit values for w array and 8 32-bit values for a array (total 288 byte)
-
-Bck1 = 12
-Bck2 = 13
-Bck3 = 14
-Bck4 = 15
-Func1 = 22
-Func2 = 23
-Func3 = 24
-Func4 = 25
-Accu1 = 16
-Accu2 = 17
-Accu3 = 18
-Accu4 = 19
-XAccu1 = 8
-XAccu2 = 9
-XAccu3 = 10
-XAccu4 = 11
-T1 = 4
-T2 = 5
-T3 = 6
-T4 = 7
-LoopC = 1
-/* byteorder: high number <--> high significance */
-sha256_nextBlock:
- ; initial, let's make some space ready for local vars
- push r4 /* replace push & pop by mem ops? */
- push r5
- push r6
- push r7
- push r8
- push r9
- push r10
- push r11
- push r12
- push r13
- push r14
- push r15
- push r16
- push r17
- push r28
- push r29
- in r20, SPL
- in r21, SPH
- movw r18, r20 ;backup SP
-; movw r26, r20 ; X points to free space on stack
- movw r30, r22 ; Z points to message
- subi r20, lo8(sha256_nextBlock_localSpace) ;sbiw can do only up to 63
- sbci r21, hi8(sha256_nextBlock_localSpace)
- movw r26, r20 ; X points to free space on stack
- in r0, SREG
- cli ; we want to be uninterrupted while updating SP
- out SPL, r20
- out SPH, r21
- out SREG, r0
- push r18
- push r19
- push r24
- push r25 /* param1 will be needed later */
- ; now we fill the w array with message (think about endianess)
- adiw r26, 1 ; X++
- ldi r20, 16
-sha256_nextBlock_wcpyloop:
- ld r23, Z+
- ld r22, Z+
- ld r19, Z+
- ld r18, Z+
- st X+, r18
- st X+, r19
- st X+, r22
- st X+, r23
- dec r20
- brne sha256_nextBlock_wcpyloop
-/* for (i=16; i<64; ++i){
- w[i] = SIGMA_b(w[i-2]) + w[i-7] + SIGMA_a(w[i-15]) + w[i-16];
- } */
- /* r25,r24,r23,r24 (r21,r20) are function values
- r19,r18,r17,r16 are the accumulator
- r15,r14,r13,rBck1 are backup1
- r11,r10,r9 ,r8 are xor accu
- r1 is round counter */
-
- ldi r20, 64-16
- mov LoopC, r20
-sha256_nextBlock_wcalcloop:
- movw r30, r26 ; cp X to Z
- sbiw r30, 63
- sbiw r30, 1 ; substract 64 = 16*4
- ld Accu1, Z+
- ld Accu2, Z+
- ld Accu3, Z+
- ld Accu4, Z+ /* w[i] = w[i-16] */
- ld Bck1, Z+
- ld Bck2, Z+
- ld Bck3, Z+
- ld Bck4, Z+ /* backup = w[i-15] */
- /* now sigma 0 */
- mov Func1, Bck2
- mov Func2, Bck3
- mov Func3, Bck4
- mov Func4, Bck1 /* prerotated by 8 */
- ldi r20, 1
- rcall bitrotl
- movw XAccu1, Func1
- movw XAccu3, Func3 /* store ROTR(w[i-15],7) in xor accu */
- movw Func1, Bck3
- movw Func3, Bck1 /* prerotated by 16 */
- ldi r20, 2
- rcall bitrotr
- eor XAccu1, Func1 /* xor ROTR(w[i-15], 18)*/
- eor XAccu2, Func2
- eor XAccu3, Func3
- eor XAccu4, Func4
- ldi Func2, 3 /* now shr3 */ /*we can destroy backup now*/
-sigma0_shr:
- lsr Bck4
- ror Bck3
- ror Bck2
- ror Bck1
- dec Func2
- brne sigma0_shr
- eor XAccu1, Bck1
- eor XAccu2, Bck2
- eor XAccu3, Bck3
- eor XAccu4, Bck4 /* xor SHR(w[i-15], 3)*/ /* xor accu == sigma1(w[i-15]) */
- add Accu1, XAccu1
- adc Accu2, XAccu2
- adc Accu3, XAccu3
- adc Accu4, XAccu4 /* finished with sigma0 */
- ldd Func1, Z+7*4 /* now accu += w[i-7] */
- ldd Func2, Z+7*4+1
- ldd Func3, Z+7*4+2
- ldd Func4, Z+7*4+3
- add Accu1, Func1
- adc Accu2, Func2
- adc Accu3, Func3
- adc Accu4, Func4
- ldd Bck1, Z+12*4 /* now backup = w[i-2]*/
- ldd Bck2, Z+12*4+1
- ldd Bck3, Z+12*4+2
- ldd Bck4, Z+12*4+3
- /* now sigma 1 */
- movw Func1, Bck3
- movw Func3, Bck1 /* prerotated by 16 */
- ldi r20, 1
- rcall bitrotr
- movw XAccu3, Func3
- movw XAccu1, Func1 /* store in ROTR(w[i-2], 17) xor accu */
-; movw Func1, Bck3
-; movw Func3, Bck1 /* prerotated by 16 */
- ldi r20, 2
- rcall bitrotr
- eor XAccu1, Func1 /* xor ROTR(w[i-2], 19)*/
- eor XAccu2, Func2
- eor XAccu3, Func3
- eor XAccu4, Func4
- ldi Func2, 2 /* now shr10 (dirty trick, skipping a byte) */ /*we can destroy backup now*/
-sigma1_shr:
- lsr Bck4
- ror Bck3
- ror Bck2
- dec Func2
- brne sigma1_shr
- eor XAccu1, Bck2
- eor XAccu2, Bck3
- eor XAccu3, Bck4 /* xor SHR(w[i-2], 10)*/ /* xor accu == sigma1(w[i-15]) */
- add Accu1, XAccu1
- adc Accu2, XAccu2
- adc Accu3, XAccu3
- adc Accu4, XAccu4 /* finished with sigma0 */
- /* now let's store the shit */
- st X+, Accu1
- st X+, Accu2
- st X+, Accu3
- st X+, Accu4
- dec LoopC
- breq 3f ; skip if zero
- rjmp sha256_nextBlock_wcalcloop
-3:
- /* we are finished with w array X points one byte post w */
-/* init a array */
- pop r31
- pop r30
- push r30
- push r31
- ldi r25, 8*4 /* 8 32-bit values to copy from ctx to a array */
-init_a_array:
- ld r1, Z+
- st X+, r1
- dec r25
- brne init_a_array
-
-/* now the real fun begins */
-/* for (i=0; i<64; ++i){
- t1 = a[7] + SIGMA1(a[4]) + CH(a[4],a[5],a[6]) + k[i] + w[i];
- t2 = SIGMA0(a[0]) + MAJ(a[0],a[1],a[2]);
- memmove(&(a[1]), &(a[0]), 7*4); // a[7]=a[6]; a[6]=a[5]; a[5]=a[4]; a[4]=a[3]; a[3]=a[2]; a[2]=a[1]; a[1]=a[0];
- a[4] += t1;
- a[0] = t1 + t2;
- } */
- /* Y points to a[0], Z ('cause lpm wants it) points to k[i], X points to w[i] */
- sbiw r26, 8*4 /* X still points at a[7]+1*/
- movw r28, r26
- ldi r30, lo8(sha256_kv)
- ldi r31, hi8(sha256_kv)
- dec r27 /* X - (64*4 == 256) */
- ldi r25, 64
- mov LoopC, r25
-sha256_main_loop:
- /* now calculate t1 */
- /*CH(x,y,z) = (x&y)^((~x)&z)*/
- ldd T1, Y+5*4
- ldd T2, Y+5*4+1
- ldd T3, Y+5*4+2
- ldd T4, Y+5*4+3 /* y in T */
- ldd Func1, Y+4*4
- ldd Func2, Y+4*4+1
- ldd Func3, Y+4*4+2
- ldd Func4, Y+4*4+3 /* x in Func */
- ldd Bck1, Y+6*4
- ldd Bck2, Y+6*4+1
- ldd Bck3, Y+6*4+2
- ldd Bck4, Y+6*4+3 /* z in Bck */
- and T1, Func1
- and T2, Func2
- and T3, Func3
- and T4, Func4
- com Func1
- com Func2
- com Func3
- com Func4
- and Bck1, Func1
- and Bck2, Func2
- and Bck3, Func3
- and Bck4, Func4
- eor T1, Bck1
- eor T2, Bck2
- eor T3, Bck3
- eor T4, Bck4 /* done, CH(x,y,z) is in T */
- /* now SIGMA1(a[4]) */
- ldd Bck4, Y+4*4 /* think about using it from Func reg above*/
- ldd Bck1, Y+4*4+1
- ldd Bck2, Y+4*4+2
- ldd Bck3, Y+4*4+3 /* load prerotate by 8-bit */
- movw Func1, Bck1
- movw Func3, Bck3
- ldi r20, 2
- rcall bitrotl /* rotr(x,6) */
- movw XAccu1, Func1
- movw XAccu3, Func3
- movw Func1, Bck1
- movw Func3, Bck3
- ldi r20, 3
- rcall bitrotr /* rotr(x,11) */
- eor XAccu1, Func1
- eor XAccu2, Func2
- eor XAccu3, Func3
- eor XAccu4, Func4
- movw Func1, Bck3 /* this prerotates furteh 16 bits*/
- movw Func3, Bck1 /* so we have now prerotated by 24 bits*/
- ldi r20, 1
- rcall bitrotr /* rotr(x,11) */
- eor XAccu1, Func1
- eor XAccu2, Func2
- eor XAccu3, Func3
- eor XAccu4, Func4 /* finished with SIGMA1, add it to T */
- add T1, XAccu1
- adc T2, XAccu2
- adc T3, XAccu3
- adc T4, XAccu4
- /* now we've to add a[7], w[i] and k[i] */
- ldd XAccu1, Y+4*7
- ldd XAccu2, Y+4*7+1
- ldd XAccu3, Y+4*7+2
- ldd XAccu4, Y+4*7+3
- add T1, XAccu1
- adc T2, XAccu2
- adc T3, XAccu3
- adc T4, XAccu4 /* add a[7] */
- ld XAccu1, X+
- ld XAccu2, X+
- ld XAccu3, X+
- ld XAccu4, X+
- add T1, XAccu1
- adc T2, XAccu2
- adc T3, XAccu3
- adc T4, XAccu4 /* add w[i] */
- lpm XAccu1, Z+
- lpm XAccu2, Z+
- lpm XAccu3, Z+
- lpm XAccu4, Z+
- add T1, XAccu1
- adc T2, XAccu2
- adc T3, XAccu3
- adc T4, XAccu4 /* add k[i] */ /* finished with t1 */
- /*now t2 = SIGMA0(a[0]) + MAJ(a[0],a[1],a[2]) */ /*i did to much x86 asm, i always see 4 32bit regs*/
- /* starting with MAJ(x,y,z) */
- ldd Func1, Y+4*0+0
- ldd Func2, Y+4*0+1
- ldd Func3, Y+4*0+2
- ldd Func4, Y+4*0+3 /* load x=a[0] */
- ldd XAccu1, Y+4*1+0
- ldd XAccu2, Y+4*1+1
- ldd XAccu3, Y+4*1+2
- ldd XAccu4, Y+4*1+3 /* load y=a[1] */
- and XAccu1, Func1
- and XAccu2, Func2
- and XAccu3, Func3
- and XAccu4, Func4 /* XAccu == (x & y) */
- ldd Bck1, Y+4*2+0
- ldd Bck2, Y+4*2+1
- ldd Bck3, Y+4*2+2
- ldd Bck4, Y+4*2+3 /* load z=a[2] */
- and Func1, Bck1
- and Func2, Bck2
- and Func3, Bck3
- and Func4, Bck4
- eor XAccu1, Func1
- eor XAccu2, Func2
- eor XAccu3, Func3
- eor XAccu4, Func4 /* XAccu == (x & y) ^ (x & z) */
- ldd Func1, Y+4*1+0
- ldd Func2, Y+4*1+1
- ldd Func3, Y+4*1+2
- ldd Func4, Y+4*1+3 /* load y=a[1] */
- and Func1, Bck1
- and Func2, Bck2
- and Func3, Bck3
- and Func4, Bck4
- eor XAccu1, Func1
- eor XAccu2, Func2
- eor XAccu3, Func3
- eor XAccu4, Func4 /* XAccu == Maj(x,y,z) == (x & y) ^ (x & z) ^ (y & z) */
- /* SIGMA0(a[0]) */
- ldd Bck1, Y+4*0+0 /* we should combine this with above */
- ldd Bck2, Y+4*0+1
- ldd Bck3, Y+4*0+2
- ldd Bck4, Y+4*0+3
- movw Func1, Bck1
- movw Func3, Bck3
- ldi r20, 2
- rcall bitrotr
- movw Accu1, Func1
- movw Accu3, Func3 /* Accu = shr(a[0], 2) */
- movw Func1, Bck3
- movw Func3, Bck1 /* prerotate by 16 bits */
- ldi r20, 3
- rcall bitrotl
- eor Accu1, Func1
- eor Accu2, Func2
- eor Accu3, Func3
- eor Accu4, Func4 /* Accu ^= shr(a[0], 13) */
- mov Func1, Bck4
- mov Func2, Bck1
- mov Func3, Bck2
- mov Func4, Bck3 /* prerotate by 24 bits */
- ldi r20, 2
- rcall bitrotl
- eor Accu1, Func1
- eor Accu2, Func2
- eor Accu3, Func3
- eor Accu4, Func4 /* Accu ^= shr(a[0], 22) */
- add Accu1, XAccu1 /* add previous result (MAJ)*/
- adc Accu2, XAccu2
- adc Accu3, XAccu3
- adc Accu4, XAccu4
- /* now we are finished with the computing stuff (t1 in T, t2 in Accu)*/
- /* a[7]=a[6]; a[6]=a[5]; a[5]=a[4]; a[4]=a[3]; a[3]=a[2]; a[2]=a[1]; a[1]=a[0]; */
-
- ldi r21, 7*4
- adiw r28, 7*4
-a_shift_loop:
- ld r25, -Y /* warning: this is PREdecrement */
- std Y+4, r25
- dec r21
- brne a_shift_loop
-
- ldd Bck1, Y+4*4+0
- ldd Bck2, Y+4*4+1
- ldd Bck3, Y+4*4+2
- ldd Bck4, Y+4*4+3
- add Bck1, T1
- adc Bck2, T2
- adc Bck3, T3
- adc Bck4, T4
- std Y+4*4+0, Bck1
- std Y+4*4+1, Bck2
- std Y+4*4+2, Bck3
- std Y+4*4+3, Bck4
- add Accu1, T1
- adc Accu2, T2
- adc Accu3, T3
- adc Accu4, T4
- std Y+4*0+0, Accu1
- std Y+4*0+1, Accu2
- std Y+4*0+2, Accu3
- std Y+4*0+3, Accu4 /* a array updated */
-
-
- dec LoopC
- breq update_state
- rjmp sha256_main_loop ;brne sha256_main_loop
-update_state:
- /* update state */
- /* pointers to state should still exist on the stack ;-) */
- pop r31
- pop r30
- ldi r21, 8
-update_state_loop:
- ldd Accu1, Z+0
- ldd Accu2, Z+1
- ldd Accu3, Z+2
- ldd Accu4, Z+3
- ld Func1, Y+
- ld Func2, Y+
- ld Func3, Y+
- ld Func4, Y+
- add Accu1, Func1
- adc Accu2, Func2
- adc Accu3, Func3
- adc Accu4, Func4
- st Z+, Accu1
- st Z+, Accu2
- st Z+, Accu3
- st Z+, Accu4
- dec r21
- brne update_state_loop
- /* now we just have to update the length */
- adiw r30, 1 /* since we add 512, we can simply skip the LSB */
- ldi r21, 2
- ldi r22, 6
- ld r20, Z
- add r20, r21
- st Z+, r20
- clr r21
-sha256_nextBlock_fix_length:
- brcc sha256_nextBlock_epilog
- ld r20, Z
- adc r20, r21
- st Z+, r20
- dec r22
- brne sha256_nextBlock_fix_length
-
-; EPILOG
-sha256_nextBlock_epilog:
-/* now we should clean up the stack */
-
- pop r21
- pop r20
- in r0, SREG
- cli ; we want to be uninterrupted while updating SP
- out SPL, r20
- out SPH, r21
- out SREG, r0
-
- clr r1
- pop r29
- pop r28
- pop r17
- pop r16
- pop r15
- pop r14
- pop r13
- pop r12
- pop r11
- pop r10
- pop r9
- pop r8
- pop r7
- pop r6
- pop r5
- pop r4
- ret
-
-sha256_kv: ; round-key-vector stored in ProgMem
-.word 0x2f98, 0x428a, 0x4491, 0x7137, 0xfbcf, 0xb5c0, 0xdba5, 0xe9b5, 0xc25b, 0x3956, 0x11f1, 0x59f1, 0x82a4, 0x923f, 0x5ed5, 0xab1c
-.word 0xaa98, 0xd807, 0x5b01, 0x1283, 0x85be, 0x2431, 0x7dc3, 0x550c, 0x5d74, 0x72be, 0xb1fe, 0x80de, 0x06a7, 0x9bdc, 0xf174, 0xc19b
-.word 0x69c1, 0xe49b, 0x4786, 0xefbe, 0x9dc6, 0x0fc1, 0xa1cc, 0x240c, 0x2c6f, 0x2de9, 0x84aa, 0x4a74, 0xa9dc, 0x5cb0, 0x88da, 0x76f9
-.word 0x5152, 0x983e, 0xc66d, 0xa831, 0x27c8, 0xb003, 0x7fc7, 0xbf59, 0x0bf3, 0xc6e0, 0x9147, 0xd5a7, 0x6351, 0x06ca, 0x2967, 0x1429
-.word 0x0a85, 0x27b7, 0x2138, 0x2e1b, 0x6dfc, 0x4d2c, 0x0d13, 0x5338, 0x7354, 0x650a, 0x0abb, 0x766a, 0xc92e, 0x81c2, 0x2c85, 0x9272
-.word 0xe8a1, 0xa2bf, 0x664b, 0xa81a, 0x8b70, 0xc24b, 0x51a3, 0xc76c, 0xe819, 0xd192, 0x0624, 0xd699, 0x3585, 0xf40e, 0xa070, 0x106a
-.word 0xc116, 0x19a4, 0x6c08, 0x1e37, 0x774c, 0x2748, 0xbcb5, 0x34b0, 0x0cb3, 0x391c, 0xaa4a, 0x4ed8, 0xca4f, 0x5b9c, 0x6ff3, 0x682e
-.word 0x82ee, 0x748f, 0x636f, 0x78a5, 0x7814, 0x84c8, 0x0208, 0x8cc7, 0xfffa, 0x90be, 0x6ceb, 0xa450, 0xa3f7, 0xbef9, 0x78f2, 0xc671
-
-
-;###########################################################
-
-.global sha256_init
-;uint32_t sha256_init_vector[]={
-; 0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A,
-; 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19 };
-;
-;void sha256_init(sha256_ctx_t *state){
-; state->length=0;
-; memcpy(state->h, sha256_init_vector, 8*4);
-;}
-; param1: (r23,r24) 16-bit pointer to sha256_ctx_t struct in ram
-; modifys: Z(r30,r31), Func1, r22
-sha256_init:
- movw r26, r24 ; (24,25) --> (26,27) load X with param1
- ldi r30, lo8((sha256_init_vector))
- ldi r31, hi8((sha256_init_vector))
- ldi r22, 32+8
-sha256_init_vloop:
- lpm r23, Z+
- st X+, r23
- dec r22
- brne sha256_init_vloop
- ret
-
-sha256_init_vector:
-.word 0xE667, 0x6A09
-.word 0xAE85, 0xBB67
-.word 0xF372, 0x3C6E
-.word 0xF53A, 0xA54F
-.word 0x527F, 0x510E
-.word 0x688C, 0x9B05
-.word 0xD9AB, 0x1F83
-.word 0xCD19, 0x5BE0
-.word 0x0000, 0x0000
-.word 0x0000, 0x0000
-
-;###########################################################
-
-.global rotl32
-; === ROTL32 ===
-; function that rotates a 32 bit word to the left
-; param1: the 32-bit word to rotate
-; given in r25,r24,r23,r22 (r25 is most significant)
-; param2: an 8-bit value telling how often to rotate
-; given in r20
-; modifys: r21, r22
-rotl32:
- cpi r20, 8
- brlo bitrotl
- mov r21, r25
- mov r25, r24
- mov r24, r23
- mov r23, r22
- mov r22, r21
- subi r20, 8
- rjmp rotl32
-bitrotl:
- clr r21
- clc
-bitrotl_loop:
- tst r20
- breq fixrotl
- rol r22
- rol r23
- rol r24
- rol r25
- rol r21
- dec r20
- rjmp bitrotl_loop
-fixrotl:
- or r22, r21
- ret
-
-
-;###########################################################
-
-.global rotr32
-; === ROTR32 ===
-; function that rotates a 32 bit word to the right
-; param1: the 32-bit word to rotate
-; given in r25,r24,r23,22 (r25 is most significant)
-; param2: an 8-bit value telling how often to rotate
-; given in r20
-; modifys: r21, r22
-rotr32:
- cpi r20, 8
- brlo bitrotr
- mov r21, r22
- mov r22, r23
- mov r23, r24
- mov r24, r25
- mov r25, r21
- subi r20, 8
- rjmp rotr32
-bitrotr:
- clr r21
- clc
-bitrotr_loop:
- tst r20
- breq fixrotr
- ror r25
- ror r24
- ror r23
- ror r22
- ror r21
- dec r20
- rjmp bitrotr_loop
-fixrotr:
- or r25, r21
- ret
-
-
-;###########################################################
-
-.global change_endian32
-; === change_endian32 ===
-; function that changes the endianess of a 32-bit word
-; param1: the 32-bit word
-; given in r25,r24,r23,22 (r25 is most significant)
-; modifys: r21, r22
-change_endian32:
- movw r20, r22 ; (r22,r23) --> (r20,r21)
- mov r22, r25
- mov r23, r24
- mov r24, r21
- mov r25, r20
- ret
-