+++ /dev/null
-/* cast5.c */
-/*
- 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/>.
-*/
-/*
- * \file cast5.c
- * \author Daniel Otte
- * \email daniel.otte@rub.de
- * \date 2006-07-26
- * \par License:
- * GPLv3 or later
- * \brief Implementation of the CAST5 (aka CAST-128) cipher algorithm as described in RFC 2144
- *
- */
-
- #include <stdint.h>
- #include <string.h>
- #include "cast5.h"
- #include "config.h"
- #include "debug.h"
-
- #undef DEBUG
-
- #ifdef DEBUG
- #include "cli.h"
- #endif
-
-#include "cast5-sbox.h"
-
-
-
-#define S5(x) pgm_read_dword(&s5[(x)])
-#define S6(x) pgm_read_dword(&s6[(x)])
-#define S7(x) pgm_read_dword(&s7[(x)])
-#define S8(x) pgm_read_dword(&s8[(x)])
-
-static
-void cast5_init_A(uint8_t *dest, uint8_t *src, bool bmode){
- uint8_t mask = bmode?0x8:0;
- *((uint32_t*)(&dest[0x0])) = *((uint32_t*)(&src[0x0^mask]))
- ^ S5(src[0xD^mask]) ^ S6(src[0xF^mask])
- ^ S7(src[0xC^mask]) ^ S8(src[0xE^mask])
- ^ S7(src[0x8^mask]);
- *((uint32_t*)(&dest[0x4])) = *((uint32_t*)(&src[0x8^mask]))
- ^ S5(dest[0x0]) ^ S6(dest[0x2])
- ^ S7(dest[0x1]) ^ S8(dest[0x3])
- ^ S8(src[0xA^mask]);
- *((uint32_t*)(&dest[0x8])) = *((uint32_t*)(&src[0xC^mask]))
- ^ S5(dest[0x7]) ^ S6(dest[0x6])
- ^ S7(dest[0x5]) ^ S8(dest[0x4])
- ^ S5(src[0x9^mask]);
- *((uint32_t*)(&dest[0xC])) = *((uint32_t*)(&src[0x4^mask]))
- ^ S5(dest[0xA])
- ^ S6(dest[0x9])
- ^ S7(dest[0xB])
- ^ S8(dest[0x8])
- ^ S6(src[0xB^mask]);
-}
-
-static
-void cast5_init_M(uint8_t *dest, uint8_t *src, bool nmode, bool xmode){
- uint8_t nmt[] = {0xB, 0xA, 0x9, 0x8,
- 0xF, 0xE, 0xD, 0xC,
- 0x3, 0x2, 0x1, 0x0,
- 0x7, 0x6, 0x5, 0x4}; /* nmode table */
- uint8_t xmt[4][4] = {{0x2, 0x6, 0x9, 0xC},
- {0x8, 0xD, 0x3, 0x7},
- {0x3, 0x7, 0x8, 0xD},
- {0x9, 0xC, 0x2, 0x6}};
- #define NMT(x) (src[nmode?nmt[(x)]:(x)])
- #define XMT(x) (src[xmt[(xmode<<1) + nmode][(x)]])
- *((uint32_t*)(&dest[0x0])) = S5(NMT(0x8)) ^ S6(NMT(0x9)) ^ S7(NMT(0x7)) ^ S8(NMT(0x6)) ^ S5(XMT(0));
- *((uint32_t*)(&dest[0x4])) = S5(NMT(0xA)) ^ S6(NMT(0xB)) ^ S7(NMT(0x5)) ^ S8(NMT(0x4)) ^ S6(XMT(1));
- *((uint32_t*)(&dest[0x8])) = S5(NMT(0xC)) ^ S6(NMT(0xD)) ^ S7(NMT(0x3)) ^ S8(NMT(0x2)) ^ S7(XMT(2));
- *((uint32_t*)(&dest[0xC])) = S5(NMT(0xE)) ^ S6(NMT(0xF)) ^ S7(NMT(0x1)) ^ S8(NMT(0x0)) ^ S8(XMT(3));
-}
-
-#define S5B(x) pgm_read_byte(3+(uint8_t*)(&s5[(x)]))
-#define S6B(x) pgm_read_byte(3+(uint8_t*)(&s6[(x)]))
-#define S7B(x) pgm_read_byte(3+(uint8_t*)(&s7[(x)]))
-#define S8B(x) pgm_read_byte(3+(uint8_t*)(&s8[(x)]))
-
-static
-void cast5_init_rM(uint8_t *klo, uint8_t *khi, uint8_t offset, uint8_t *src, bool nmode, bool xmode){
- uint8_t nmt[] = {0xB, 0xA, 0x9, 0x8, 0xF, 0xE, 0xD, 0xC, 0x3, 0x2, 0x1, 0x0, 0x7, 0x6, 0x5, 0x4}; /* nmode table */
- uint8_t xmt[4][4] = {{0x2, 0x6, 0x9, 0xC}, {0x8, 0xD, 0x3, 0x7}, {0x3, 0x7, 0x8, 0xD}, {0x9, 0xC, 0x2, 0x6}};
- uint8_t t, h=0;
- t = S5B(NMT(0x8)) ^ S6B(NMT(0x9)) ^ S7B(NMT(0x7)) ^ S8B(NMT(0x6)) ^ S5B(XMT(0));
- klo[offset*2] |= (t & 0x0f);
- h |= (t&0x10); h>>=1;
- t = S5B(NMT(0xA)) ^ S6B(NMT(0xB)) ^ S7B(NMT(0x5)) ^ S8B(NMT(0x4)) ^ S6B(XMT(1));
- klo[offset*2] |= (t<<4) & 0xf0;
- h |= t&0x10; h>>=1;
- t = S5B(NMT(0xC)) ^ S6B(NMT(0xD)) ^ S7B(NMT(0x3)) ^ S8B(NMT(0x2)) ^ S7B(XMT(2));
- klo[offset*2+1] |= t&0xf;
- h |= t&0x10; h>>=1;
- t = S5B(NMT(0xE)) ^ S6B(NMT(0xF)) ^ S7B(NMT(0x1)) ^ S8B(NMT(0x0)) ^ S8B(XMT(3));
- klo[offset*2+1] |= t<<4;
- h |= t&0x10; h >>=1;
- #ifdef DEBUG
- cli_putstr("\r\n\t h="); cli_hexdump(&h,1);
- #endif
- khi[offset>>1] |= h<<((offset&0x1)?4:0);
-}
-
-#define S_5X(s) pgm_read_dword(&s5[BPX[(s)]])
-#define S_6X(s) pgm_read_dword(&s6[BPX[(s)]])
-#define S_7X(s) pgm_read_dword(&s7[BPX[(s)]])
-#define S_8X(s) pgm_read_dword(&s8[BPX[(s)]])
-
-#define S_5Z(s) pgm_read_dword(&s5[BPZ[(s)]])
-#define S_6Z(s) pgm_read_dword(&s6[BPZ[(s)]])
-#define S_7Z(s) pgm_read_dword(&s7[BPZ[(s)]])
-#define S_8Z(s) pgm_read_dword(&s8[BPZ[(s)]])
-
-
-
-
-void cast5_init(const void* key, uint16_t keylength_b, cast5_ctx_t* s){
- /* we migth return if the key is valid and if setup was successful */
- uint32_t x[4], z[4];
- #define BPX ((uint8_t*)&(x[0]))
- #define BPZ ((uint8_t*)&(z[0]))
- s->shortkey = (keylength_b<=80);
- /* littel endian only! */
- memset(&(x[0]), 0 ,16); /* set x to zero */
- if(keylength_b > 128)
- keylength_b=128;
- memcpy(&(x[0]), key, (keylength_b+7)/8);
-
-
- /* todo: merge a and b and compress the whole stuff */
- /***** A *****/
- cast5_init_A((uint8_t*)(&z[0]), (uint8_t*)(&x[0]), false);
- /***** M *****/
- cast5_init_M((uint8_t*)(&(s->mask[0])), (uint8_t*)(&z[0]), false, false);
- /***** B *****/
- cast5_init_A((uint8_t*)(&x[0]), (uint8_t*)(&z[0]), true);
- /***** N *****/
- cast5_init_M((uint8_t*)(&(s->mask[4])), (uint8_t*)(&x[0]), true, false);
- /***** A *****/
- cast5_init_A((uint8_t*)(&z[0]), (uint8_t*)(&x[0]), false);
- /***** N' *****/
- cast5_init_M((uint8_t*)(&(s->mask[8])), (uint8_t*)(&z[0]), true, true);
- /***** B *****/
- cast5_init_A((uint8_t*)(&x[0]), (uint8_t*)(&z[0]), true);
- /***** M' *****/
- cast5_init_M((uint8_t*)(&(s->mask[12])), (uint8_t*)(&x[0]), false, true);
-
- /* that were the masking keys, now the rotation keys */
- /* set the keys to zero */
- memset(&(s->rotl[0]),0,8);
- s->roth[0]=s->roth[1]=0;
- /***** A *****/
- cast5_init_A((uint8_t*)(&z[0]), (uint8_t*)(&x[0]), false);
- /***** M *****/
- cast5_init_rM(&(s->rotl[0]), &(s->roth[0]), 0, (uint8_t*)(&z[0]), false, false);
- /***** B *****/
- cast5_init_A((uint8_t*)(&x[0]), (uint8_t*)(&z[0]), true);
- /***** N *****/
- cast5_init_rM(&(s->rotl[0]), &(s->roth[0]), 1, (uint8_t*)(&x[0]), true, false);
- /***** A *****/
- cast5_init_A((uint8_t*)(&z[0]), (uint8_t*)(&x[0]), false);
- /***** N' *****/
- cast5_init_rM(&(s->rotl[0]), &(s->roth[0]), 2, (uint8_t*)(&z[0]), true, true);
- /***** B *****/
- cast5_init_A((uint8_t*)(&x[0]), (uint8_t*)(&z[0]), true);
- /***** M' *****/
- cast5_init_rM(&(s->rotl[0]), &(s->roth[0]), 3, (uint8_t*)(&x[0]), false, true);
- /* done ;-) */
-}
-
-
-
-/********************************************************************************************************/
-
-#define ROTL32(a,n) ((a)<<(n) | (a)>>(32-(n)))
-#define CHANGE_ENDIAN32(x) ((x)<<24 | (x)>>24 | ((x)&0xff00)<<8 | ((x)&0xff0000)>>8 )
-
-typedef uint32_t cast5_f_t(uint32_t,uint32_t,uint8_t);
-
-#define IA 3
-#define IB 2
-#define IC 1
-#define ID 0
-
-static
-uint32_t cast5_f1(uint32_t d, uint32_t m, uint8_t r){
- uint32_t t;
- t = ROTL32((d + m),r);
-#ifdef DEBUG
- uint32_t ia,ib,ic,id;
- cli_putstr("\r\n f1("); cli_hexdump(&d, 4); cli_putc(',');
- cli_hexdump(&m , 4); cli_putc(','); cli_hexdump(&r, 1);cli_putstr("): I=");
- cli_hexdump(&t, 4);
- ia = pgm_read_dword(&s1[((uint8_t*)&t)[IA]] );
- ib = pgm_read_dword(&s2[((uint8_t*)&t)[IB]] );
- ic = pgm_read_dword(&s3[((uint8_t*)&t)[IC]] );
- id = pgm_read_dword(&s4[((uint8_t*)&t)[ID]] );
- cli_putstr("\r\n\tIA="); cli_hexdump(&ia, 4);
- cli_putstr("\r\n\tIB="); cli_hexdump(&ib, 4);
- cli_putstr("\r\n\tIC="); cli_hexdump(&ic, 4);
- cli_putstr("\r\n\tID="); cli_hexdump(&id, 4);
-
- return (((ia ^ ib) - ic) + id);
-
-#else
-
- return ((( pgm_read_dword(&s1[((uint8_t*)&t)[IA]])
- ^ pgm_read_dword(&s2[((uint8_t*)&t)[IB]]) )
- - pgm_read_dword(&s3[((uint8_t*)&t)[IC]]) )
- + pgm_read_dword(&s4[((uint8_t*)&t)[ID]]) );
-
-#endif
-}
-
-static
-uint32_t cast5_f2(uint32_t d, uint32_t m, uint8_t r){
- uint32_t t;
- t = ROTL32((d ^ m),r);
-#ifdef DEBUG
- uint32_t ia,ib,ic,id;
- cli_putstr("\r\n f2("); cli_hexdump(&d, 4); cli_putc(',');
- cli_hexdump(&m , 4); cli_putc(','); cli_hexdump(&r, 1);cli_putstr("): I=");
- cli_hexdump(&t, 4);
-
- ia = pgm_read_dword(&s1[((uint8_t*)&t)[IA]] );
- ib = pgm_read_dword(&s2[((uint8_t*)&t)[IB]] );
- ic = pgm_read_dword(&s3[((uint8_t*)&t)[IC]] );
- id = pgm_read_dword(&s4[((uint8_t*)&t)[ID]] );
-
- cli_putstr("\r\n\tIA="); cli_hexdump(&ia, 4);
- cli_putstr("\r\n\tIB="); cli_hexdump(&ib, 4);
- cli_putstr("\r\n\tIC="); cli_hexdump(&ic, 4);
- cli_putstr("\r\n\tID="); cli_hexdump(&id, 4);
-
- return (((ia - ib) + ic) ^ id);
-#else
-
- return ((( pgm_read_dword(&s1[((uint8_t*)&t)[IA]])
- - pgm_read_dword(&s2[((uint8_t*)&t)[IB]]) )
- + pgm_read_dword(&s3[((uint8_t*)&t)[IC]]) )
- ^ pgm_read_dword(&s4[((uint8_t*)&t)[ID]]) );
-
-#endif
-}
-
-static
-uint32_t cast5_f3(uint32_t d, uint32_t m, uint8_t r){
- uint32_t t;
- t = ROTL32((m - d),r);
-
-#ifdef DEBUG
- uint32_t ia,ib,ic,id;
-
- cli_putstr("\r\n f3("); cli_hexdump(&d, 4); cli_putc(',');
- cli_hexdump(&m , 4); cli_putc(','); cli_hexdump(&r, 1);cli_putstr("): I=");
- cli_hexdump(&t, 4);
-
- ia = pgm_read_dword(&s1[((uint8_t*)&t)[IA]] );
- ib = pgm_read_dword(&s2[((uint8_t*)&t)[IB]] );
- ic = pgm_read_dword(&s3[((uint8_t*)&t)[IC]] );
- id = pgm_read_dword(&s4[((uint8_t*)&t)[ID]] );
-
- cli_putstr("\r\n\tIA="); cli_hexdump(&ia, 4);
- cli_putstr("\r\n\tIB="); cli_hexdump(&ib, 4);
- cli_putstr("\r\n\tIC="); cli_hexdump(&ic, 4);
- cli_putstr("\r\n\tID="); cli_hexdump(&id, 4);
- return (((ia + ib) ^ ic) - id);
-#else
- return (( pgm_read_dword(&s1[((uint8_t*)&t)[IA]] )
- + pgm_read_dword(&s2[((uint8_t*)&t)[IB]] ))
- ^ pgm_read_dword(&s3[((uint8_t*)&t)[IC]] ))
- - pgm_read_dword(&s4[((uint8_t*)&t)[ID]] );
-
-#endif
-}
-
-/******************************************************************************/
-
-void cast5_enc(void* block, const cast5_ctx_t *s){
- uint32_t l,r, x, y;
- uint8_t i;
- cast5_f_t* f[]={cast5_f1,cast5_f2,cast5_f3};
- l=((uint32_t*)block)[0];
- r=((uint32_t*)block)[1];
-// cli_putstr("\r\n round[-1] = ");
-// cli_hexdump(&r, 4);
- for (i=0;i<(s->shortkey?12:16);++i){
- x = r;
- y = (f[i%3])(CHANGE_ENDIAN32(r), CHANGE_ENDIAN32(s->mask[i]),
- (((s->roth[i>>3]) & (1<<(i&0x7)))?0x10:0x00)
- + ( ((s->rotl[i>>1])>>((i&1)?4:0)) & 0x0f) );
- r = l ^ CHANGE_ENDIAN32(y);
-// cli_putstr("\r\n round["); DEBUG_B(i); cli_putstr("] = ");
-// cli_hexdump(&r, 4);
- l = x;
- }
- ((uint32_t*)block)[0]=r;
- ((uint32_t*)block)[1]=l;
-}
-
-/******************************************************************************/
-
-void cast5_dec(void* block, const cast5_ctx_t *s){
- uint32_t l,r, x, y;
- int8_t i, rounds;
- cast5_f_t* f[]={cast5_f1,cast5_f2,cast5_f3};
- l=((uint32_t*)block)[0];
- r=((uint32_t*)block)[1];
- rounds = (s->shortkey?12:16);
- for (i=rounds-1; i>=0 ;--i){
- x = r;
- y = (f[i%3])(CHANGE_ENDIAN32(r), CHANGE_ENDIAN32(s->mask[i]),
- (((s->roth[i>>3]) & (1<<(i&0x7)))?0x10:0x00)
- + ( ((s->rotl[i>>1])>>((i&1)?4:0)) & 0x0f) );
- r = l ^ CHANGE_ENDIAN32(y);
- l = x;
- }
- ((uint32_t*)block)[0]=r;
- ((uint32_t*)block)[1]=l;
-}
-
-
-/******************************************************************************/
-
-
-
-
projects / avr-crypto-lib.git / blobdiff