+/* keysize_descriptor.c */
+/*
+ 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/>.
+*/
+/**
+ * \file keysize_descriptor.c
+ * \author Daniel Otte
+ * \email daniel.otte@rub.de
+ * \date 2009-01-07
+ * \license GPLv3 or later
+ */
+
+#include <stdint.h>
+#include <stdlib.h>
+#include "keysize_descriptor.h"
+
+uint8_t is_valid_keysize_P(const void* ks_desc, uint16_t keysize){
+ uint8_t type;
+ type = *((uint8_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 1;
+ if(type==KS_TYPE_TERMINATOR)
+ return 0;
+ if(type==KS_TYPE_LIST){
+ uint8_t items;
+ uint16_t item;
+ items = *((uint8_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 1;
+ while(items--){
+ item = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ if(item==keysize)
+ return 1;
+ }
+ ks_desc = (uint8_t*)ks_desc - 2;
+ }
+ if(type==KS_TYPE_RANGE){
+ uint16_t max, min;
+ min = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ max = *((uint16_t*)ks_desc);
+ if(min<=keysize && keysize<=max)
+ return 1;
+ }
+ if(type==KS_TYPE_ARG_RANGE){
+ uint16_t max, min, dist, offset;
+ min = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ max = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ dist = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ offset = *((uint16_t*)ks_desc);
+ if(min<=keysize && keysize<=max && (keysize%dist==offset))
+ return 1;
+ }
+ if(type>KS_TYPE_ARG_RANGE){
+ /* bad error, you may insert a big warning message here */
+ return 0;
+ }
+ return is_valid_keysize_P((uint8_t*)ks_desc+1, keysize); /* search the next record */
+}
+
+uint16_t get_keysize(const void* ks_desc){
+ uint8_t type;
+ uint16_t keysize;
+ type = *((uint8_t*)ks_desc);
+ if(type==KS_TYPE_LIST){
+ ks_desc = (uint8_t*)ks_desc + 1;
+ }
+ ks_desc = (uint8_t*)ks_desc + 1;
+ keysize = *((uint8_t*)ks_desc);
+ return keysize;
+}
+
+uint16_t get_keysizes(const void* ks_desc, uint16_t** list){
+ uint8_t type;
+ uint16_t items;
+ uint8_t i;
+ type = *((uint8_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 1;
+ if(type==KS_TYPE_LIST){
+ items = *((uint8_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 1;
+ if(!*list){
+ *list = malloc(items*2);
+ if(!*list){
+ return 0;
+ }
+ }
+ for(i=0; i<items; ++i){
+ ((uint16_t*)(*list))[i] = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ }
+ return items;
+ }
+ if(type==KS_TYPE_ARG_RANGE){
+ uint16_t min, max, distance, offset;
+ min = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ max = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ distance = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ offset = *((uint16_t*)ks_desc);
+ items = (max-min)/distance+1;
+ if(min%distance!=offset){
+ --items;
+ min += (distance-(min%distance-offset))%distance;
+ }
+ if(!*list){
+ *list = malloc(items*2);
+ if(!*list){
+ return 0;
+ }
+ }
+ i=0;
+ while(min<max){
+ ((uint16_t*)*list)[i++] = min;
+ min += distance;
+ }
+ return i;
+ }
+ if(type==KS_TYPE_RANGE){
+ uint16_t min, max, distance=8, offset=0;
+ min = *((uint16_t*)ks_desc);
+ ks_desc = (uint8_t*)ks_desc + 2;
+ max = *((uint16_t*)ks_desc);
+ items = (max-min)/distance+1;
+ if(min%distance!=offset){
+ --items;
+ min += (distance-(min%distance-offset))%distance;
+ }
+ if(!*list){
+ *list = malloc(items*2);
+ if(!*list){
+ return 0;
+ }
+ }
+ i=0;
+ while(min<max){
+ ((uint16_t*)*list)[i++] = min;
+ min += distance;
+ }
+ return i;
+ }
+ return 0;
+}