javarsa代码 java代码例子讲解( 五 )


my $N=new Math::BigInt($RSA_CORE{n});
my $E=new Math::BigInt($RSA_CORE{e});
my $D=new Math::BigInt($RSA_CORE{d});
print "N=$N D=$D E=$E\n";
sub RSA_ENCRYPT
{
my $r_mess = shift @_;
my ($c,$i,$M,$C,$cmess);
for($i=0;$ilength($$r_mess);$i++)
{
$c=ord(substr($$r_mess,$i,1));
$M=Math::BigInt-new($c);
$C=$M-copy(); $C-bmodpow($D,$N);
$c=sprintf "%03X",$C;
$cmess.=$c;
}
return \$cmess;
}
sub RSA_DECRYPT
{
my $r_mess = shift @_;
my ($c,$i,$M,$C,$dmess);
for($i=0;$ilength($$r_mess);$i+=3)
{
$c=substr($$r_mess,$i,3);
$c=hex($c);
$M=Math::BigInt-new($c);
$C=$M-copy(); $C-bmodpow($E,$N);
$c=chr($C);
$dmess.=$c;
}
return \$dmess;
}
my $mess="RSA 娃哈哈哈~~~";
$mess=$ARGV[0] if @ARGV = 1;
print "原始串:",$mess,"\n";
my $r_cmess = RSA_ENCRYPT(\$mess);
print "加密串:",$$r_cmess,"\n";
my $r_dmess = RSA_DECRYPT($r_cmess);
print "解密串:",$$r_dmess,"\n";
#EOF
测试一下:
C:\Tempperl rsa-test.pl
N=2773D=847E=63
原始串:RSA 娃哈哈哈~~~
加密串:5CB6CD6BC58A7709470AA74A0AA74A0AA74A6C70A46C70A46C70A4
解密串:RSA 娃哈哈哈~~~
C:\Tempperl rsa-test.pl 安全焦点(xfocus)
N=2773D=847E=63
原始串:安全焦点(xfocus)
加密串:3393EC12F0A466E0AA9510D025D7BA0712DC3379F47D51C325D67B
解密串:安全焦点(xfocus)
四提高
前面已经提到,rsa的安全来源于n足够大,我们测试中使用的n是非常小的 , 根本不能保障安全性,
我们可以通过RSAKit、RSATool之类的工具获得足够大的N 及D E 。
通过工具,我们获得1024位的N及D E来测试一下:
n=0x328C74784DF31119C526D18098EBEBB943B0032B599CEE13CC2BCE7B5FCD15F90B66EC3A85F5005D
BDCDED9BDFCB3C4C265AF164AD55884D8278F791C7A6BFDAD55EDBC4F017F9CCF1538D4C2013433B383B
47D80EC74B51276CA05B5D6346B9EE5AD2D7BE7ABFB36E37108DD60438941D2ED173CCA50E114705D7E2
BC511951
d=0x10001
e=0xE760A3804ACDE1E8E3D7DC0197F9CEF6282EF552E8CEBBB7434B01CB19A9D87A3106DD28C523C2995
4C5D86B36E943080E4919CA8CE08718C3B0930867A98F635EB9EA9200B25906D91B80A47B77324E66AFF2
C4D70D8B1C69C50A9D8B4B7A3C9EE05FFF3A16AFC023731D80634763DA1DCABE9861A4789BD782A592D2B
1965
设原始信息
M=0x11111111111122222222222233333333333
完成这么大数字的计算依赖于大数运算库 , 用perl来运算非常简单:
A) 用d对M进行加密如下:
c=M**d%n :
C:\Tempperl -Mbigint -e " $x=Math::BigInt-bmodpow(0x11111111111122222222222233
333333333, 0x10001, 0x328C74784DF31119C526D18098EBEBB943B0032B599CEE13CC2BCE7B5F
CD15F90B66EC3A85F5005DBDCDED9BDFCB3C4C265AF164AD55884D8278F791C7A6BFDAD55EDBC4F0
17F9CCF1538D4C2013433B383B47D80EC74B51276CA05B5D6346B9EE5AD2D7BE7ABFB36E37108DD6
0438941D2ED173CCA50E114705D7E2BC511951);print $x-as_hex"
0x17b287be418c69ecd7c39227ab681ac422fcc84bb35d8a632543b304de288a8d4434b73d2576bd
45692b007f3a2f7c5f5aa1d99ef3866af26a8e876712ed1d4cc4b293e26bc0a1dc67e247715caa6b
3028f9461a3b1533ec0cb476441465f10d8ad47452a12db0601c5e8beda686dd96d2acd59ea89b91
f1834580c3f6d90898
即用d对M加密后信息为:
c=0x17b287be418c69ecd7c39227ab681ac422fcc84bb35d8a632543b304de288a8d4434b73d2576bd
45692b007f3a2f7c5f5aa1d99ef3866af26a8e876712ed1d4cc4b293e26bc0a1dc67e247715caa6b
3028f9461a3b1533ec0cb476441465f10d8ad47452a12db0601c5e8beda686dd96d2acd59ea89b91
f1834580c3f6d90898
B) 用e对c进行解密如下:
m=c**e%n :
C:\Tempperl -Mbigint -e " $x=Math::BigInt-bmodpow(0x17b287be418c69ecd7c39227ab
681ac422fcc84bb35d8a632543b304de288a8d4434b73d2576bd45692b007f3a2f7c5f5aa1d99ef3
866af26a8e876712ed1d4cc4b293e26bc0a1dc67e247715caa6b3028f9461a3b1533ec0cb4764414

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