//密鑰生成器源文件

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <tomcrypt.h>
#pragma link "tomcrypt.lib"

int main(int argc, char* argv[])
{



    printf("Rinick 橢圓曲線密鑰生成器，程序使用tomcrypt加密函數庫\n\n");

    if(fopen("private_key.c", "rb")!=NULL){
        printf("錯誤！\nprivate_key.c已存在，為了防止誤刪，請手動刪除\n\n");
        system("pause");
        return 0;
    }


    char tempChar[90];

    //隨機數狀態初始化
    int pn=register_prng(&rc4_desc);//隨機數生成方式，可以選擇其他方式，參考crypt.pdf第56頁
    prng_state tg;
    prng_descriptor[pn].start(&tg);

    printf("輸入一些內容來擾亂隨機數，輸入0系統會自動分配隨機數\n?:");
    scanf("%64s",tempChar);
    if(tempChar[0]=='0' && tempChar[1]==0){

        int getrand;
        prng_descriptor[pn].add_entropy((char*)&getrand,2,&tg);
        for(int i=0;i<5;++i){
            srand(time(NULL));
            for(int j=0;j<5;++j){
                getrand=rand();
                prng_descriptor[pn].add_entropy((char*)&getrand,2,&tg);
            }
        }

    }else{
        while(tempChar[0]!='0' || tempChar[1]!=0){
            prng_descriptor[pn].add_entropy(tempChar,strlen(tempChar),&tg);
            printf("你還可以繼續輸入來增加隨機性，輸入0終止初始化\n?:");
            scanf("%64s",tempChar);
        }
    }
    prng_descriptor[pn].ready(&tg);

    int ecclen;
    printf("\n\n選擇橢圓曲線\n可以是192,224,256,384,521\n?:");
    scanf("%d",&ecclen);
    ecclen/=8;
		if(ecclen>65)ecclen=65;

    ecc_key ekey1;
    ecc_make_key(&tg,pn,ecclen,&ekey1);

    FILE *out=fopen("private_key.c", "wt");


    fputs("ltc_ecc_mykey.type=PK_PRIVATE;\n",out);
    fprintf(out,"ltc_ecc_mykey.idx=%d;\n",ekey1.idx);
    fputs("mp_init_multi(&ltc_ecc_mykey.pubkey.x, &ltc_ecc_mykey.pubkey.y, &ltc_ecc_mykey.pubkey.z, &ltc_ecc_mykey.k, NULL);\n",out);

    mp_toradix (&ekey1.pubkey.x, tempChar, 64);
    fprintf(out,"mp_read_radix(&ltc_ecc_mykey.pubkey.x, \"%s\", 64);\n",tempChar);

    mp_toradix (&ekey1.pubkey.y, tempChar, 64);
    fprintf(out,"mp_read_radix(&ltc_ecc_mykey.pubkey.y, \"%s\", 64);\n",tempChar);

    fputs("mp_set(&ltc_ecc_mykey.pubkey.z, 1);\n",out);

    mp_toradix (&ekey1.k, tempChar, 64);
    fprintf(out,"mp_read_radix(&ltc_ecc_mykey.k, \"%s\", 64);\n",tempChar);

    fclose(out);

    out=fopen("public_key.c", "wt");


    fputs("ltc_ecc_mykey.type=PK_PUBLIC;\n",out);
    fprintf(out,"ltc_ecc_mykey.idx=%d;\n",ekey1.idx);
    fputs("mp_init_multi(&ltc_ecc_mykey.pubkey.x, &ltc_ecc_mykey.pubkey.y, &ltc_ecc_mykey.pubkey.z, &ltc_ecc_mykey.k, NULL);\n",out);

    mp_toradix (&ekey1.pubkey.x, tempChar, 64);
    fprintf(out,"mp_read_radix(&ltc_ecc_mykey.pubkey.x, \"%s\", 64);\n",tempChar);

    mp_toradix (&ekey1.pubkey.y, tempChar, 64);
    fprintf(out,"mp_read_radix(&ltc_ecc_mykey.pubkey.y, \"%s\", 64);\n",tempChar);

    fputs("mp_set(&ltc_ecc_mykey.pubkey.z, 1);\n",out);
		fputs("mp_set(&ltc_ecc_mykey.k, 0);\n",out);
    fclose(out);
    printf("\n你的密鑰信息保存在private_key.c中，公鑰信息保存在public_key.c，請將這兩個文件復制到工程目錄下并妥善備份\n\n");

    system("pause");
    return 0;
}