一个简单的公私钥加密算法

#include <ctime>

#include <iostream>#include <cstdlib>using namespace std;struct public_key{int  n;int  x;};struct private_key{int p;int q;};int  power(int x,int y,int m)//cal x^y%m{if(y==0)return 1%m;int  ret=x%m;for(int i=0;i<y-1;i++)ret=(ret*x)%m;return ret;}int get_x(int p,int q){for(int i=1;i<p*q;i++){if (power(i,(p-1)/2,p)==p-1&&power(i,(q-1)/2,q)==q-1){cout<<"get x:"<<i<<endl;return i;}}}void get_key(public_key* bk,private_key* rk,int p,int q){bk->n=p*q;bk->x=get_x(p,q);rk->p=p;rk->q=q;}int get_random(int n){srand(unsigned(time(0)));int ret=rand()%1000;int max,min;if(ret>=n){max=ret;min=n;}else {max=n;min=ret;}while(min){int tmp=max%min;if(tmp==1)return  ret;max=min;min=tmp;}}int encrypt(int src,int n,int x){int y=get_random(n);cout<<"get y:"<<y<<endl;return (power(y,2,n)*power(x,src,n))%n;}int decode(int src,int p,int q){int cp=power(src,(p-1)/2,p);int cq=power(src,(q-1)/2,q);cout<<"c/p="<<cp<<endl;cout<<"c/q="<<cq<<endl;if(cp==1&&cq==1) return 0;else return 1;}int main(){public_key* bk=new public_key;private_key* rk=new private_key;int p=613,q=827;get_key(bk,rk,p,q);int src=1;cout<<"1:\n";int enc=encrypt(src,bk->n,bk->x);cout<<"encrypt:"<<enc<<endl;cout<<"m':"<<decode(enc,rk->p,rk->q)<<endl;src=0;cout<<"0:\n";enc=encrypt(src,bk->n,bk->x);cout<<"encrypt:"<<enc<<endl;cout<<"m':"<<decode(enc,rk->p,rk->q)<<endl;return 0;}