开始不知道有BigInteger这个大数类
居然自己去实现了个写了大数加法后才发现有现成
T_T以下是引用片段:
package rsa;
import java.math.BigInteger;
public
RSA { private long p,q,e,d,n;
public RSA
{ 
pIndex = ()(Math.random*10); qIndex; eIndex; do{
qIndex = (
)(Math.random*10); }
while(qIndex
pIndex); do{
eIndex = (
)(Math.random*10); }
while(eIndex
pIndex||eIndexpIndex); p = 1033;
q = 2017;
e = 29437;
n = p*q;
d = calculateD
; }
private long calculateD
{ long t0 = 0,t1 = 1,t2 = -1;
long r0 = (p-1)*(q-1), m = r0,r1 = e ,r2 = -1;
do{
long q = r0/r1;
r2 = r0-r1*q;
(r20)
; t2 = t0 - t1*q;
while(t2<0){
t2
m; }
(t2>=m){ t2 %= m;
}
r0 = r1;
r1 = r2;
t0 = t1;
t1 = t2;
}while(r2!=0);
(r1!=1){ 
0; }
{ t2; }
}
public long getE
{ e; }
public long getN
{ n; }
public long getD
{ d; }
public BigInteger encode(BigInteger data){
pow(data,d).mod(
BigInteger(n+"")); }
public BigInteger decode(BigInteger code){
pow(code,e).mod( BigInteger(n+"")); }
public BigInteger pow(BigInteger data,long p){
data = data.pow((
)p); data; }
public
void 
(String args
){ RSA rsa =
RSA; BigInteger data =
BigInteger("222222"); long oldtime =
.currentTimeMillis; BigInteger code = rsa.encode(data);
long
time = .currentTimeMillis; double codetime = ((double)(
time-oldtime))/1000; oldtime =
.currentTimeMillis; BigInteger decode = rsa.decode(code);
time = .currentTimeMillis; double decodetime = ((double)(
time-oldtime))/1000; .out.prln("privateKey:"+rsa.d); .out.prln("publickKey:"+rsa.e); .out.prln("N:"+rsa.n); .out.prln("data:"+data); .out.prln("code:"+code+" time:"+codetime); .out.prln("decode:"+decode+" time:"+decodetime); }
}
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