--- /dev/null
+/* ubi256_asm.S */
+/*
+ This file is part of the AVR-Crypto-Lib.
+ Copyright (C) 2009 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
+ * \email daniel.otte@rub.de
+ * \date 2009-03-16
+ * \license GPLv3 or later
+ */
+
+#include "avr-asm-macros.S"
+
+/******************************************************************************/
+/*
+void ubi256_init(ubi256_ctx_t* ctx, const void* g, uint8_t type){
+ memset(ctx->tweak, 0, 15);
+ ctx->tweak[15] = 0x40+type;
+ memcpy(ctx->g, g, 32);
+}
+*/
+/*
+ * param ctx: r24:r25
+ * param g: r22:r23
+ * param type: r20
+ */
+.global ubi256_init
+ubi256_init:
+ movw r26, r24
+ ldi r21, 15
+1: st X+, r1
+ dec r21
+ brne 1b
+ ori r20, 0x40
+ st X+, r20
+ ldi r21, 32
+ movw r30, r22
+2: ld r20, Z+
+ st X+, r20
+ dec r21
+ brne 2b
+ ret
+
+/******************************************************************************/
+/*
+void ubi256_ctx2hash(void* dest, const ubi256_ctx_t* ctx){
+ memcpy(dest, ctx->g, UBI256_BLOCKSIZE_B);
+}
+*/
+/*
+ * param dest: r24:r24
+ * param ctx: r22:r23
+ */
+.global ubi256_ctx2hash
+ubi256_ctx2hash:
+ movw r26, r24
+ movw r30, r22
+ adiw r30, 16
+ ldi r22, 32
+1: ld r23, Z+
+ st X+, r23
+ dec r22
+ brne 1b
+ ret
+
+/******************************************************************************/
+/*
+void ubi256_nextBlock(ubi256_ctx_t* ctx, const void* block){
+ threefish256_ctx_t tfctx;
+ ((uint64_t*)(ctx->tweak))[0] += UBI256_BLOCKSIZE_B;
+ threefish256_init(ctx->g, ctx->tweak, &tfctx);
+ memcpy(ctx->g, block, UBI256_BLOCKSIZE_B);
+ threefish256_enc(ctx->g, &tfctx);
+ memxor(ctx->g, block, UBI256_BLOCKSIZE_B);
+ ctx->tweak[15] &= (uint8_t)~0x40;
+}
+*/
+/*
+ * param ctx: r24:r25
+ * param block: r22:r23
+ */
+CTX0 = 2
+CTX1 = 3
+BLOCK0 = 4
+BLOCK1 = 5
+TFCTX0 = 6
+TFCTX1 = 7
+.global ubi256_nextBlock
+ubi256_nextBlock:
+ stack_alloc_large 64
+ push_range 2, 7
+ adiw r30, 1 /* Z points to tfctx */
+ movw TFCTX0, r30
+ movw CTX0, r24
+ movw BLOCK0, r22
+ movw r26, r24
+/* add BLOCKSIZE_B (32) to tweak */
+ ldi r25, 32
+ ld r24, X
+ add r24, r25
+ st X+, r24
+ ldi r25, 11
+1: ld r24, X
+ adc r24, r1
+ st X+, r24
+ dec r25
+ brne 1b
+/* call threefish256_init */
+ movw r24, CTX0
+ adiw r24, 16
+ movw r22, CTX0
+ movw CTX0, r24 /* CTX points to ctx->g */
+ movw r20, TFCTX0
+ rcall threefish256_init
+ /* copy block to ctx->g */
+ movw r26, CTX0
+ movw r30, BLOCK0
+ ldi r25, 32
+1: ld r24, Z+
+ st X+, r24
+ dec r25
+ brne 1b
+/* call threefish256_enc */
+ movw r24, CTX0
+ movw r22, TFCTX0
+ rcall threefish256_enc
+/* xor block into ctx->g */
+ movw r26, BLOCK0
+ movw r30, CTX0
+ ldi r25, 32
+1: ld r24, X+
+ ld r23, Z
+ eor r23, r24
+ st Z+, r23
+ dec r25
+ brne 1b
+/* clear 'first' bit in tweak */
+ sbiw r30, 33
+ ld r24, Z
+ andi r24, ~0x40
+ st Z, r24
+exit:
+ pop_range 2, 7
+ stack_free_large 64
+ ret
+
+/******************************************************************************/
+/*
+void ubi256_lastBlock(ubi256_ctx_t* ctx, const void* block, uint16_t length_b){
+ threefish256_ctx_t tfctx;
+ while(length_b>UBI256_BLOCKSIZE){
+ ubi256_nextBlock(ctx, block);
+ block = (uint8_t*)block + UBI256_BLOCKSIZE_B;
+ length_b -= UBI256_BLOCKSIZE;
+ }
+ ctx->tweak[15] |= 0x80;
+ ((uint64_t*)(ctx->tweak))[0] += (length_b+7)/8;
+ if(length_b & 0x07){
+ ctx->tweak[14] |= 0x80;
+ }
+ threefish256_init(ctx->g, ctx->tweak, &tfctx);
+ memset(ctx->g, 0, UBI256_BLOCKSIZE_B);
+ memcpy(ctx->g, block, (length_b+7)/8);
+ if(length_b & 0x07){
+ ctx->g[((length_b+7)/8)-1] |= 0x80>>(length_b&7);
+ ctx->g[((length_b+7)/8)-1] &= ~((0x80>>(length_b&7))-1);
+ }
+ threefish256_enc(ctx->g, &tfctx);
+ memxor(ctx->g, block, (length_b+7)/8);
+ if(length_b & 0x07){
+ ctx->g[((length_b+7)/8)-1] ^= 0x80>>(length_b&7);
+ }
+}
+*/
+/*
+ * param ctx: r24:r25
+ * param block: r22:r23
+ * param ength_b: r20:r21
+ */
+MASK_B = 8
+LEN_B = 9
+TFCTX0 = 10
+TFCTX1 = 11
+CTX0 = 12
+CTX1 = 13
+BLOCK0 = 14
+BLOCK1 = 15
+LENGTH0 = 16
+LENGTH1 = 17
+.global ubi256_lastBlock
+ubi256_lastBlock:
+/* run nextBlock for preceding blocks*/
+ push_range 8, 17
+ movw CTX0, r24
+ movw BLOCK0, r22
+ movw LENGTH0, r20
+1: cpi LENGTH1, 2
+ brlo 2f
+ movw r24, CTX0
+ movw r22, BLOCK0
+ rcall ubi256_nextBlock
+ ldi r25, 32
+ add BLOCK0, r25
+ adc BLOCK1, r1
+ dec LENGTH1
+ rjmp 1b
+2: tst LENGTH1
+ breq 3f
+ tst LENGTH0
+ breq 3f
+ movw r24, CTX0
+ movw r22, BLOCK0
+ rcall ubi256_nextBlock
+ ldi r25, 32
+ add BLOCK0, r25
+ adc BLOCK1, r1
+ dec LENGTH1
+3: /* now the real fun */
+ stack_alloc_large 64
+ adiw r30, 1
+ movw TFCTX0, r30
+ /* calculate LEN_B */
+ movw r24, LENGTH0
+ adiw r24, 7
+ lsr r25
+ ror r24
+ lsr r24
+ lsr r24
+ mov LEN_B, r24
+ /* add length to tweak */
+ movw r30, CTX0
+ ld r24, Z
+ add r24, LEN_B
+ st Z+, r24
+ ldi r25, 11
+1: ld r24, Z
+ adc r24, r1
+ st Z+, r24
+ dec r25
+ brne 1b
+ /* set 'final' bit*/
+ movw r30, CTX0
+ ldd r24, Z+15
+ ori r24, 0x80
+ std Z+15, r24
+ /* store in T if we do bit processing and set 'BitPad' bit*/
+ clr MASK_B
+ mov r24, LENGTH0
+ andi r24, 0x07
+ tst r24
+ breq 4f
+ ldd r25, Z+14
+ ori r25, 0x80
+ std Z+14, r25
+ ldi r25, 0x80
+ mov MASK_B, r25
+1: lsr MASK_B
+ dec r24
+ brne 1b
+4: /* call threefish256_init*/
+ movw r24, CTX0
+ adiw r24, 16
+ movw r22, CTX0
+ movw CTX0, r24 /* CTX points at ctx->g */
+ movw r20, TFCTX0
+ rcall threefish256_init
+ /* copy block to ctx->g */
+ movw r26, BLOCK0
+ movw r30, CTX0
+ mov r24, LEN_B
+ ldi r25, 32
+ sub r25, LEN_B
+ tst r24
+1: breq 2f
+ ld r22, X+
+ st Z+, r22
+ dec r24
+ rjmp 1b
+2: tst MASK_B
+ breq 29f
+ or r22, MASK_B
+ st -Z, r22
+ adiw r30, 1
+29: tst r25
+3: breq 4f
+ st Z+, r1
+ dec r25
+ rjmp 3b
+4: /* call threefish256_enc */
+ movw r24, CTX0
+ movw r22, TFCTX0
+ rcall threefish256_enc
+ /* xor block into ctx->g */
+ movw r30, CTX0
+ movw r26, BLOCK0
+ tst LEN_B
+5: breq 6f
+ ld r22, X+
+ ld r23, Z
+ eor r23, r22
+ st Z+, r23
+ dec LEN_B
+ rjmp 5b
+6: tst MASK_B
+ breq 7f
+ eor r23, MASK_B
+ st -Z, r23
+
+7: stack_free_large 64
+ pop_range 8, 17
+ ret
+
+
projects / avr-crypto-lib.git / blobdiff