⭐ 欢迎来到虫虫下载站! | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站

📄 bigint.cpp

📁 RSA公钥加密算法(基于大整数的分解难实现的
💻 CPP
字号:
#include"iostream.h"
#include"stdlib.h"
#include"time.h"
#include"math.h"
#include"string.h"

#define MAXLEN 40

class BigInt
{
public:
  int Sign;                                  
  int Length;                                
  unsigned long value[MAXLEN];               

  BigInt();
  BigInt(int S,int L);
  ~BigInt();

  BigInt& Mov(BigInt& A);
  void Mov(unsigned __int64 A); 
  int Cmp(BigInt& A);
  BigInt Add(BigInt& A);
  BigInt Add(unsigned long A); 
  BigInt Sub(BigInt& A);
  BigInt Sub(unsigned long A); 
  BigInt Mul(BigInt& A);
  BigInt Mul(unsigned long A);
  BigInt Div(BigInt& A);
  BigInt Div(unsigned long A);
  BigInt Mod(BigInt& A);
  unsigned long Mod(unsigned long A); 
  BigInt RsaMon(BigInt& A, BigInt& B); 
  BigInt Euc(BigInt& A);
  void Get(char* Str);
  //void produce(BigInt& A);
 // int Neql(BigInt& A);
 // void Put(BigInt& A);

};


BigInt::BigInt()
{
Sign=1;
Length=1;
for(int i=0;i<MAXLEN;i++)  value[i]=0;
}

BigInt::BigInt(int S,int L)
{
Sign=S;
Length=L;
for(int i=0;i<Length;i++)  value[i]=0;
}


BigInt::~BigInt()
{
}

int BigInt::Cmp(BigInt& A)
{
if(Length>A.Length)return 1;
if(Length<A.Length)return -1;
for(int i=Length-1;i>=0;i--)
{
if(value[i]>A.value[i])return 1;
if(value[i]<A.value[i])return -1;
}
return 0;
}


BigInt& BigInt::Mov(BigInt& A)
{
Length=A.Length;
for(int i=0;i<MAXLEN;i++)  value[i]=A.value[i];
return *this;
}

void BigInt::Mov(unsigned __int64 A) 
{ 
    if(A>0xffffffff) 
    { 
        Length=2; 
        value[1]=(unsigned long)(A>>32); 
        value[0]=(unsigned long)A; 
    } 
    else 
    { 
        Length=1; 
        value[0]=(unsigned long)A; 
    } 
    for(int i=Length;i<MAXLEN;i++)
		value[i]=0; 
}


BigInt BigInt::Add(BigInt& A)
{
BigInt X;
if(X.Sign==A.Sign) 
{
X.Mov(*this);
int carry=0;
    unsigned __int64 sum=0;
    if(X.Length<A.Length)X.Length=A.Length;
for(int i=0;i<X.Length;i++)
{
sum=A.value[i];
sum=sum+X.value[i]+carry;
X.value[i]=(unsigned long)sum;
if(sum>0xffffffff)carry=1;
else carry=0;
}
if(X.Length<MAXLEN)
{
X.value[X.Length]=carry;
  X.Length+=carry;
}
return X;
}
else{X.Mov(A);X.Sign=1-X.Sign;return Sub(X);}
}

BigInt BigInt::Add(unsigned long A) 
{ 
    BigInt X; 
    X.Mov(*this); 
    unsigned __int64 sum; 
    sum=X.value[0]; 
   sum+=A; 
    X.value[0]=(unsigned long)sum; 
    if(sum>0xffffffff) 
    { 
        int i=1; 
        while(X.value[i]==0xffffffff){X.value[i]=0;i++;} 
        X.value[i]++; 
        if(Length==i)Length++; 
    } 
    return X; 
}


BigInt BigInt::Sub(BigInt& A)
{
BigInt X;
if(Sign==A.Sign)
{
X.Mov(*this);
int cmp=X.Cmp(A); 
if(cmp==0){X.Mov(0);return X;}
int len,carry=0;
unsigned __int64 num;
unsigned long *s,*d;
    if(cmp>0)
          {
              s=X.value;
              d=A.value;
              len=X.Length;
          }
    if(cmp<0)
          { 
              s=A.value;
              d=X.value;
              len=A.Length;
              X.Sign=1-X.Sign;
          }
    for(int i=0;i<len;i++)
{
if((s[i]-carry)>=d[i])
{
X.value[i]=s[i]-carry-d[i];
carry=0;
}
else
{
num=0x100000000+s[i];
X.value[i]=(unsigned long)(num-carry-d[i]);
carry=1;
}
}
while(X.value[len-1]==0)len--;
X.Length=len;
return X;
}
else{X.Mov(A);X.Sign=1-X.Sign;return Add(X);}
}
 
BigInt BigInt::Sub(unsigned long A) 
{ 
    BigInt X; 
    X.Mov(*this); 
    if(X.value[0]>=A){X.value[0]-=A;return X;} 
    if(X.Length==1){X.Mov(0);return X;} 
    unsigned __int64 num=0x100000000+X.value[0]; 
    X.value[0]=(unsigned long)(num-A); 
    int i=1; 
    while(X.value[i]==0){X.value[i]=0xffffffff;i++;} 
    X.value[i]--; 
    if(X.value[i]==0)X.Length--; 
    return X; 
} 



BigInt BigInt::Mul(BigInt& A)
{
BigInt X,Y;
unsigned __int64 mul;
    unsigned long carry;
    for(int i=0;i<A.Length;i++)
{
Y.Length=Length;
carry=0;
for(int j=0;j<Length;j++)
{
mul=value[j];
mul=mul*A.value[i]+carry;
Y.value[j]=(unsigned long)mul;
carry=(unsigned long)(mul>>32);
}
if(carry&&(Y.Length<MAXLEN))
          {
              Y.Length++;
              Y.value[Y.Length-1]=carry;
          }
if(Y.Length<MAXLEN-i)
{
Y.Length+=i;
    for(int k=Y.Length-1;k>=i;k--)Y.value[k]=Y.value[k-i];
    for(k=0;k<i;k++)Y.value[k]=0;
}
X.Mov(X.Add(Y));
}
if(Sign+A.Sign==1)X.Sign=0;
else X.Sign=1;
return X;
}

BigInt BigInt::Mul(unsigned long A) 
{ 
    BigInt X; 
    unsigned __int64 mul; 
    unsigned long carry=0; 
    X.Mov(*this); 
    for(int i=0;i<Length;i++) 
    { 
        mul=value[i]; 
        mul=mul*A+carry; 
        X.value[i]=(unsigned long)mul; 
        carry=(unsigned long)(mul>>32); 
    } 
    if(carry){X.Length++;X.value[X.Length-1]=carry;} 
    return X; 
} 


BigInt BigInt::Div(BigInt& A) 
{ 
    if(A.Length==1)return Div(A.value[0]); 
    BigInt X,Y,Z; 
    unsigned i,len; 
    unsigned __int64 num,div; 
    Y.Mov(*this); 
    while(Y.Cmp(A)>=0) 
    {        
      div=Y.value[Y.Length-1]; 
      num=A.value[A.Length-1]; 
      len=Y.Length-A.Length; 
      if((div==num)&&(len==0)){X.Mov(X.Add(1));break;} 
      if((div<=num)&&len){len--;div=(div<<32)+Y.value[Y.Length-2];} 
      div=div/(num+1); 
      Z.Mov(div); 
      if(len) 
      { 
         Z.Length+=len; 
         for(i=Z.Length-1;i>=len;i--)Z.value[i]=Z.value[i-len]; 
         for(i=0;i<len;i++)Z.value[i]=0; 
      } 
      X.Mov(X.Add(Z)); 
        Y.Mov(Y.Sub(A.Mul(Z))); 
    } 
    return X; 
} 

BigInt BigInt::Div(unsigned long A) 
{ 
    BigInt X; 
    X.Mov(*this); 
    if(X.Length==1){X.value[0]=X.value[0]/A;return X;} 
    unsigned __int64 div,mul; 
    unsigned long carry=0; 
    for(int i=X.Length-1;i>=0;i--) 
    { 
        div=carry; 
        div=(div<<32)+X.value[i]; 
        X.value[i]=(unsigned long)(div/A); 
        mul=(div/A)*A; 
        carry=(unsigned long)(div-mul); 
    } 
    if(X.value[X.Length-1]==0)X.Length--; 
    return X; 
} 

BigInt BigInt::Mod(BigInt& A) 
{ 
    BigInt X,Y; 
   unsigned __int64 div,num; 
    unsigned long carry=0; 
   unsigned i,len; 
    X.Mov(*this); 
    while(X.Cmp(A)>=0) 
    { 
      div=X.value[X.Length-1]; 
      num=A.value[A.Length-1]; 
      len=X.Length-A.Length; 
      if((div==num)&&(len==0)){X.Mov(X.Sub(A));break;} 
      if((div<=num)&&len){len--;div=(div<<32)+X.value[X.Length-2];} 
      div=div/(num+1); 
      Y.Mov(div); 
      Y.Mov(A.Mul(Y)); 
      if(len) 
      { 
         Y.Length+=len; 
         for(i=Y.Length-1;i>=len;i--)Y.value[i]=Y.value[i-len]; 
         for(i=0;i<len;i++)Y.value[i]=0; 
      } 
        X.Mov(X.Sub(Y)); 
    } 
    return X; 
} 

unsigned long BigInt::Mod(unsigned long A) 
{ 
    if(Length==1)return(value[0]%A); 
    unsigned __int64 div; 
    unsigned long carry=0; 
    for(int i=Length-1;i>=0;i--) 
    { 
        div=value[i]; 
      div+=carry*0x100000000; 
        carry=(unsigned long)(div%A); 
    } 
    return carry; 
} 


BigInt BigInt::RsaMon(BigInt& A, BigInt& B) 
{
	BigInt X,Y,Z;
	X.Mov(1);
	Y.Mov(*this);
       Z.Mov(A);
	while((Z.Length!=1)||Z.value[0])
		{
			if(Z.value[0]&1)
			{
				Z.Mov(Z.Sub(1));
				X.Mov(X.Mul(Y));
				X.Mov(X.Mod(B));
			}
			else
			{
				Z.Mov(Z.Div(2));
				Y.Mov(Y.Mul(Y));
				Y.Mov(Y.Mod(B));
			}
		}
  return X;
}

BigInt BigInt::Euc(BigInt& A) 
{ 
   BigInt M,E,X,Y,I,J; 
    int x,y; 
   M.Mov(A); 
   E.Mov(*this); 
   X.Mov(0); 
   Y.Mov(1); 
   x=y=1; 
   while((E.Length!=1)||(E.value[0]!=0)) 
   { 
      I.Mov(M.Div(E)); 
      J.Mov(M.Mod(E)); 
      M.Mov(E); 
      E.Mov(J); 
      J.Mov(Y); 
      Y.Mov(Y.Mul(I)); 
      if(x==y) 
      { 
          if(X.Cmp(Y)>=0)Y.Mov(X.Sub(Y)); 
         else{Y.Mov(Y.Sub(X));y=0;} 
      } 
      else{Y.Mov(X.Add(Y));x=1-x;y=1-y;} 
      X.Mov(J); 
   } 
   if(x==0)X.Mov(A.Sub(X)); 
   return X; 
} 

void Put(BigInt& A)
{
	for(int i=A.Length-1;i>=0;i--)
	{
		cout<<A.value[i];
    	if(i==0)
			cout<<endl<<"*********************************信息安全2班***********************************"<<endl;
	}


}
void produce(BigInt& A)
{
	srand(unsigned long(time(NULL)));
	A.value[0]=rand();

}

int set(BigInt X,BigInt Y,BigInt N)
{	
	X.Mul(Y);
	X.Mod(N);
	if(X.value[0]==1&&X.value[1]==0) return 1;
	else return 0;

}

/*unsigned long gcd(unsigned long m,BigInt& n)
	{
		BigInt r,x;
		x.value[0]=m;
		while(Neql(x)!=0)
		{
			r.Mov(n.Mod(x));
			n.Mov(x);
			x.Mov(r);
		
		}
		m=n.value[0];
		return m;
	}
*/

int Neql(BigInt& A)
{
	if(A.value[0]==0&&A.value[1]==0)
	return 0;
	else 
	return 1;
}


unsigned long Gcd(BigInt m,BigInt n)
{
	BigInt r;
	unsigned long j=0;
	if(m.Cmp(n)==1)
	{
		r.Mov(n);
		n.Mov(m);
		m.Mov(r);

	}
		while(Neql(m)!=0)
		{
			r.Mov(n.Mod(m));   //r=n%m;
			n.Mov(m);          //n=m;
			m.Mov(r);   //m=r;
		
		}
		j=n.value[0];
		return j;
}
/*		temp.Mov(n);
		for(int i=temp.Length-1;i>=0;i--) 
			if(temp.value[i]==0)
			{
				n.Length--;
				break;
			}
		return (unsigned long)n;

  }  
unsigned long inveser(BigInt& A)
{
	unsigned long *x;
	*x=A.value[0];
		return *x;
}
*/
void BigInt::Get(char* Str)
{   
    int len=strlen(Str),k; 
    Mov(0); 
	
    for(int i=0;i<len;i++) 
    { 
       Mov(Mul(10));
       if((Str[i]>='0')&&(Str[i]<='9'))
		   k=Str[i]-48; 
       else k=0; 
       Mov(Add(k)); 

    } 
} 
/*void BigInt::Solve(BigInt& A)
{
	unsigned long k;
	BigInt X,Y;
	X.Mov(A);
		while(A.value[A.Length-1]==0) A.Length--;
		if(A.Length==1)  break;
		for(int i=0;i<=A.Length-1;i++)
		{

			A.Mov(A.Sub(0x100000000)); 
			X.value[i]=A.value[0];
		}

}
*/
int main()
{
	BigInt p(1,5),q(1,5),n(1,10),N(1,10),e,m,c,D,d(1,6);
	char *S;
	char *Z;
	char *W;
	char *T;
    S=new char[1280];
    Z=new char[1280];
	W=new char[1280];
	T=new char[1280];
	cout<<"please input the BigInt p:";
	cin>>S;
	p.Get(S);
	cout<<"the BigInt p is:"<<endl;
		Put(p);

	cout<<"please input the BigInt q:";
	cin>>Z;
	q.Get(Z);
	cout<<"the BigInt q is:"<<endl;
		Put(q);

	n.Mov(p.Mul(q));
	N.Mov((p.Sub(1)).Mul(q.Sub(1)));

	cout<<"N is "<<endl;
	Put(N);

	cout<<"the BigInt n is:"<<endl;
		Put(n);


     for(int i=101;i<=1001;i++)
		{	
		    d.Mov(i);
			if(Gcd(d,N)==1)
			{
				cout<<"the BigInt d is:";
		        break;
			}
		 }

	 cout<<"与N互素的随机整数:"<<endl;
		Put(d);

for(unsigned long y=3;y<101;y++)
{
    e.Mov(d.Euc(N));
	if(set(e,d,N)==1) break;

}
cout<<"the BigInt e is:"<<endl;
		Put(e);	

	cout<<"请输入您要加密的信息:"<<endl;
	cin>>T;
	m.Get(T);
	cout<<"您输入的明文数字串为:"<<endl;
		Put(m);
    c.Mov(m.RsaMon(e,n));
	cout<<"经加密后的信息为:"<<endl;
		Put(c);
	D.Mov(c.RsaMon(d,n));
	cout<<"经解密后的数字串为:"<<endl;
		Put(D);

cout<<endl<<"*********************************信息安全2班***********************************"<<endl;
	cout<<"@退出请按 q 键@";
	cin>>W;
	if(W=="q")  exit(1);
		delete S;
		delete Z;
		delete W;
		delete T;
	return 0;

}	
/*
//小素数表 
const static int PrimeTable[550]= 
{   3,    5,    7,    11,   13,   17,   19,   23,   29,   31, 
    37,   41,   43,   47,   53,   59,   61,   67,   71,   73, 
    79,   83,   89,   97,   101,  103,  107,  109,  113,  127, 
    131,  137,  139,  149,  151,  157,  163,  167,  173,  179, 
    181,  191,  193,  197,  199,  211,  223,  227,  229,  233, 
    239,  241,  251,  257,  263,  269,  271,  277,  281,  283, 
    293,  307,  311,  313,  317,  331,  337,  347,  349,  353, 
    359,  367,  373,  379,  383,  389,  397,  401,  409,  419, 
    421,  431,  433,  439,  443,  449,  457,  461,  463,  467, 
    479,  487,  491,  499,  503,  509,  521,  523,  541,  547, 
    557,  563,  569,  571,  577,  587,  593,  599,  601,  607, 
    613,  617,  619,  631,  641,  643,  647,  653,  659,  661, 
    673,  677,  683,  691,  701,  709,  719,  727,  733,  739, 
    743,  751,  757,  761,  769,  773,  787,  797,  809,  811, 
    821,  823,  827,  829,  839,  853,  857,  859,  863,  877, 
    881,  883,  887,  907,  911,  919,  929,  937,  941,  947, 
    953,  967,  971,  977,  983,  991,  997,  1009, 1013, 1019, 
    1021, 1031, 1033, 1039, 1049, 1051, 1061, 1063, 1069, 1087, 
    1091, 1093, 1097, 1103, 1109, 1117, 1123, 1129, 1151, 1153, 
    1163, 1171, 1181, 1187, 1193, 1201, 1213, 1217, 1223, 1229, 
    1231, 1237, 1249, 1259, 1277, 1279, 1283, 1289, 1291, 1297, 
    1301, 1303, 1307, 1319, 1321, 1327, 1361, 1367, 1373, 1381, 
    1399, 1409, 1423, 1427, 1429, 1433, 1439, 1447, 1451, 1453, 
    1459, 1471, 1481, 1483, 1487, 1489, 1493, 1499, 1511, 1523, 
    1531, 1543, 1549, 1553, 1559, 1567, 1571, 1579, 1583, 1597, 
    1601, 1607, 1609, 1613, 1619, 1621, 1627, 1637, 1657, 1663, 
    1667, 1669, 1693, 1697, 1699, 1709, 1721, 1723, 1733, 1741, 
    1747, 1753, 1759, 1777, 1783, 1787, 1789, 1801, 1811, 1823, 
    1831, 1847, 1861, 1867, 1871, 1873, 1877, 1879, 1889, 1901, 
    1907, 1913, 1931, 1933, 1949, 1951, 1973, 1979, 1987, 1993, 
    1997, 1999, 2003, 2011, 2017, 2027, 2029, 2039, 2053, 2063, 
    2069, 2081, 2083, 2087, 2089, 2099, 2111, 2113, 2129, 2131, 
    2137, 2141, 2143, 2153, 2161, 2179, 2203, 2207, 2213, 2221, 
    2237, 2239, 2243, 2251, 2267, 2269, 2273, 2281, 2287, 2293, 
    2297, 2309, 2311, 2333, 2339, 2341, 2347, 2351, 2357, 2371, 
    2377, 2381, 2383, 2389, 2393, 2399, 2411, 2417, 2423, 2437, 
    2441, 2447, 2459, 2467, 2473, 2477, 2503, 2521, 2531, 2539, 
    2543, 2549, 2551, 2557, 2579, 2591, 2593, 2609, 2617, 2621, 
    2633, 2647, 2657, 2659, 2663, 2671, 2677, 2683, 2687, 2689, 
    2693, 2699, 2707, 2711, 2713, 2719, 2729, 2731, 2741, 2749, 
    2753, 2767, 2777, 2789, 2791, 2797, 2801, 2803, 2819, 2833, 
    2837, 2843, 2851, 2857, 2861, 2879, 2887, 2897, 2903, 2909, 
    2917, 2927, 2939, 2953, 2957, 2963, 2969, 2971, 2999, 3001, 
    3011, 3019, 3023, 3037, 3041, 3049, 3061, 3067, 3079, 3083, 
    3089, 3109, 3119, 3121, 3137, 3163, 3167, 3169, 3181, 3187, 
    3191, 3203, 3209, 3217, 3221, 3229, 3251, 3253, 3257, 3259, 
    3271, 3299, 3301, 3307, 3313, 3319, 3323, 3329, 3331, 3343, 
    3347, 3359, 3361, 3371, 3373, 3389, 3391, 3407, 3413, 3433, 
    3449, 3457, 3461, 3463, 3467, 3469, 3491, 3499, 3511, 3517, 
    3527, 3529, 3533, 3539, 3541, 3547, 3557, 3559, 3571, 3581, 
    3583, 3593, 3607, 3613, 3617, 3623, 3631, 3637, 3643, 3659, 
    3671, 3673, 3677, 3691, 3697, 3701, 3709, 3719, 3727, 3733, 
    3739, 3761, 3767, 3769, 3779, 3793, 3797, 3803, 3821, 3823, 
    3833, 3847, 3851, 3853, 3863, 3877, 3881, 3889, 3907, 3911, 
    3917, 3919, 3923, 3929, 3931, 3943, 3947, 3967, 3989, 4001 
}; 
*/

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -