RSA.zip_D-H_Love T.K.O_RSA字母

#include <stdio.h> #include <stdlib.h> #include <time.h> int p, q, e, d; //p, q是两个大素数， e是公开秘钥，d是保密的解密秘钥 int Euclid(int n, int u) { //Euclid算法 int n1, n2, b1, b2, q, r, t; n1 = n; n2 = u; b1 = 0; b2 = 1; q = n1 / n2; r = n1 - q * n2; while(r!=0) { n1 = n2; n2 = r; t = b2; b2 = b1 - q * b2; b1 = t; q = n1 / n2; r = n1 - q * n2; } if(n2!=1) { printf("%d模%d不存在逆元!\n", u, n); exit(0); }else { while(b2<0||b2>n) { if(b2<0) { b2 += n; }else { b2 -= n; } } printf("%d模%d的逆元为%d\n", u, n, b2); } return b2; } int Miller_Rabin(int n) { //利用Miller_Rabin素性测试法测试一个大数是否为素数 int p = n - 1; int s = 0; int m, i, b, r, z=0, is; m = p; if(m%2==1) { printf("%d是偶数\n", p); exit(0); } while((m-m/2*2)==0) { m = m / 2; s++; } srand( (unsigned)time( NULL ) ); for(i=0; i<20; i++) { z=0; while(z==0) { b = rand(); while(b>=n) { b = b - n; } z = b; } r = 0; for(is=1; is<m; is++) { z = z * b; while(z>n) { z = z - n; } } while(z!=n-1&&z!=1) { if(r==s-1) { return 0; }else { r++; z = z * z - z * z / n * n; } } } printf("%d是素数\n", n); return 1; } int mod_cal(int m, int k, int n) { //m的k次方mod n的运算 int i, t; t = m; for(i=1; i<k; i++) { t = t * m; while(t > n) { t = t - n; } } return t; } int gcd(int m, int n) { //辗转相除法 int p; if(n > m) { p = n; n = m; m = p; } p = m % n; if(p==0) { return n; }else { gcd(n, p); } } int RSA_encryp() { //RSA加密 return 0; } int main() { int n, non_n, c, m, i = 99999; char encryption[] = "I LOVE NANJING UNIVERSITY OF AERONAUTICS AND ASTRONAUTICS"; char decryption[60], encryptext[60]; int cryp[60]; printf("********************************************************************************\n"); printf(" RSA加密\n\n"); printf("********************************************************************************\n\n"); printf("请输入素数q:"); scanf("%d", &q); getchar(); while(Miller_Rabin(q)==0) { printf("%d 不是素数!请重输:", q); scanf("%d", &q); getchar(); } printf("\n请输入素数p:"); scanf("%d", &p); getchar(); while(Miller_Rabin(p)==0) { printf("%d 不是素数", p); scanf("%d", &p); getchar(); } printf("\n"); n = p * q; non_n = (p-1) * (q-1); srand( (unsigned)time( NULL ) ); e = rand(); e = e % non_n; while(gcd(e,non_n)!=1) { e = rand(); e = e % non_n; } d = Euclid(non_n, e); printf("e:%d\t", e); printf("d:%d\n\n", d); i = 0; while(encryption[i]!='\0') { if(encryption[i]==' ') { m = 0; }else { m = encryption[i] - 'A' + 1; } c = mod_cal(m, e, n); cryp[i] = c; c = c % 26; if(c==0) { decryption[i] = ' '; }else { decryption[i] = 'A' + c -1; } i++; } decryption[i] = '\0'; printf("明文:%s\n", encryption); printf("密文:%s\n", decryption); printf("解密:"); i = 0; while(decryption[i]!='\0') { c = mod_cal(cryp[i], d, n); c = c % 26; if(c==0) { encryptext[i] = ' '; }else { encryptext[i] = 'A' + c -1; } i++; } encryptext[i] = '\0'; printf("%s\n", encryptext); return 0; }