DES简介:
DES算法为密码体制中的对称密码体制,又被成为美国数据加密标准,是1972年美国IBM公司研制的对称密码体制加密算法。其密钥长度为56位,明文按64位进行分组,将分组后的明文组和56位的密钥按位替代或交换的方法形成密文组的加密方法。DES加密算法特点:分组比较短、密钥太短、密码生命周期短、运算速度较慢。DES工作的基本原理是,其入口参数有三个:key、data、mode。 key为加密解密使用的密钥,data为加密解密的数据,mode为其工作模式。当模式为加密模式时,明文按照64位进行分组,形成明文组,key用于对数据加密,当模式为解密模式时,key用于对数据解密。实际运用中,密钥只用到了64位中的56位,这样才具有高的安全性。DES( Data Encryption Standard)算法,于1977年得到美国政府的正式许可,是一种用56位密钥来加密64位数据的方法。虽然56位密钥的DES算法已经风光不在,而且常有用Des加密的明文被破译的报道,但是了解一下昔日美国的标准加密算法总是有益的,而且目前DES算法得到了广泛的应用,在某些场合,仍然发挥着余热。
DES加密算法代码如下:
public class DesEncrypt { /*static final是表示了只读,切能在同一个进程空间内的多个 Instance间共享*/ // private static String strDefaultKey = "87654321"; public String digestHexStr; //28 static final int pc_1_cp[]={ 57,49,41,33,25,17,9 ,1,58,50,42,34,26,18 ,10,2,59,51,43,35,27 ,19,11,3,60,52,44,36}; //28 static final int pc_1_dp[]={ 63,55,47,39,31,23,15 ,7,62,54,46,38,30,22 ,14,6,61,53,45,37,29 ,21,13,5,28,20,12,4}; //48 static final int pc_2p[]={ 14,17,11,24,1,5, 3,28,15,6,21,10, 23,19,12,4,26,8, 16,7,27,20,13,2, 41,52,31,37,47,55, 30,40,51,45,33,48, 44,49,39,56,34,53, 46,42,50,36,29,32}; //16 static final int ls_countp[]={1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1}; //64 static final int iip_tab_p[]={ 58,50,42,34,26,18,10,2, 60,52,44,36,28,20,12,4, 62,54,46,38,30,22,14,6, 64,56,48,40,32,24,16,8, 57,49,41,33,25,17,9,1, 59,51,43,35,27,19,11,3, 61,53,45,37,29,21,13,5, 63,55,47,39,31,23,15,7}; //64 static final int _iip_tab_p[]={ 40,8,48,16,56,24,64,32, 39,7,47,15,55,23,63,31, 38,6,46,14,54,22,62,30, 37,5,45,13,53,21,61,29, 36,4,44,12,52,20,60,28, 35,3,43,11,51,19,59,27, 34,2,42,10,50,18,58,26, 33,1,41,9,49,17,57,25}; //48 static final int e_r_p[]={ 32,1,2,3,4,5,4,5,6,7,8,9, 8,9,10,11,12,13,12,13,14,15,16,17, 16,17,18,19,20,21,20,21,22,23,24,25, 24,25,26,27,28,29,28,29,30,31,32,1}; //32 static final int local_PP[]={ 16,7,20,21,29,12,28,17, 1,15,23,26,5,18,31,10, 2,8,24,14,32,27,3,9, 19,13,30,6,22,11,4,25}; //[8][4][16] static final int ccom_SSS_p[][][]={ {{14,4,13,1,2,15,11,8,3,10,6,12,5,9,0,7}, {0,15,7,4,14,2,13,1,10,6,12,11,9,5,3,8}, {4,1,14,8,13,6,2,11,15,12,9,7,3,10,5,0}, {15,12,8,2,4,9,1,7,5,11,3,14,10,0,6,13}}, {{15,1,8,14,6,11,3,4,9,7,2,13,12,0,5,10}, {3,13,4,7,15,2,8,14,12,0,1,10,6,9,11,5}, {0,14,7,11,10,4,13,1,5,8,12,6,9,3,2,15}, {13,8,10,1,3,15,4,2,11,6,7,12,0,5,14,9}}, {{10,0,9,14,6,3,15,5,1,13,12,7,11,4,2,8}, {13,7,0,9,3,4,6,10,2,8,5,14,12,11,15,1}, {13,6,4,9,8,15,3,0,11,1,2,12,5,10,14,7}, {1,10,13,0,6,9,8,7,4,15,14,3,11,5,2,12}}, {{7,13,14,3,0,6,9,10,1,2,8,5,11,12,4,15}, {13,8,11,5,6,15,0,3,4,7,2,12,1,10,14,9}, {10,6,9,0,12,11,7,13,15,1,3,14,5,2,8,4}, {3,15,0,6,10,1,13,8,9,4,5,11,12,7,2,14}}, /* err on */ {{2,12,4,1,7,10,11,6,8,5,3,15,13,0,14,9}, {14,11,2,12,4,7,13,1,5,0,15,10,3,9,8,6}, /* err on */ {4,2,1,11,10,13,7,8,15,9,12,5,6,3,0,14}, {11,8,12,7,1,14,2,13,6,15,0,9,10,4,5,3}}, {{12,1,10,15,9,2,6,8,0,13,3,4,14,7,5,11}, {10,15,4,2,7,12,9,5,6,1,13,14,0,11,3,8}, {9,14,15,5,2,8,12,3,7,0,4,10,1,13,11,6}, {4,3,2,12,9,5,15,10,11,14,1,7,6,0,8,13}}, {{4,11,2,14,15,0,8,13,3,12,9,7,5,10,6,1}, {13,0,11,7,4,9,1,10,14,3,5,12,2,15,8,6}, {1,4,11,13,12,3,7,14,10,15,6,8,0,5,9,2}, {6,11,13,8,1,4,10,7,9,5,0,15,14,2,3,12}}, {{13,2,8,4,6,15,11,1,10,9,3,14,5,0,12,7}, {1,15,13,8,10,3,7,4,12,5,6,11,0,14,9,2}, {7,11,4,1,9,12,14,2,0,6,10,13,15,3,5,8}, {2,1,14,7,4,10,8,13,15,12,9,0,3,5,6,11}}}; byte[][] C=new byte[17][28]; byte[][] D=new byte[17][28]; byte[][] K=new byte[17][48]; public DesEncrypt() { return; } /*iu2b把int转换成byte */ private static byte iu2b ( int input) { byte output1; output1 = (byte)(input & 0xff); return output1; } /* b2iu把byte按照不考虑正负号的原则的"升位"成int程序, 因为java没有unsigned运算 */ private static int b2iu(byte b) { return b < 0 ? b & 0x7F + 128 : b; } /*byteHEX(),用来把一个byte类型的数转换成十六进制的ASCII表示, 因为java中的byte的toString无法实现这一点,我们又没有C语言中的 sprintf(outbuf,"%02X",ib) */ public static String byteHEX(byte ib) { char[] Digit = { '0','1','2','3','4','5','6','7','8','9', 'A','B','C','D','E','F' }; char[] ob = new char[2]; ob[0] = Digit[(ib >>> 4) & 0X0F]; ob[1] = Digit[ib & 0X0F]; String s = new String(ob); return s; } /* desMemcpy是一个内部使用的byte数组的块拷贝函数, 从input的inpos开始把len长度的 字节拷贝到output的outpos位置开始 */ private void desMemcpy (byte[] output, byte[] input, int outpos, int inpos, int len) { int i; for (i = 0; i < len; i++) output[outpos + i] = input[inpos + i]; } private void Fexpand0(byte[] in,byte[] out) { int divide; int i,j; byte temp1; for (i=0;i<8;i++) { divide=7; for (j=0;j<8;j++) { temp1=in[i]; out[8*i+j]=iu2b((b2iu(temp1)>>>divide)&1); divide--; } } } private void FLS(byte[] bits,byte[] buffer,int count) { int i,j; for (i=0;i<28;i++) { buffer[i]=bits[(i+count)%28]; } } private void Fson(byte[] cc,byte[] dd,byte[] kk) { int i,j; byte[] buffer=new byte[56]; for (i=0;i<28;i++) buffer[i]=cc[i]; for (i=28;i<56;i++) buffer[i]=dd[i-28]; for (i=0;i<48;i++) kk[i]=buffer[pc_2p[i]-1]; } private void Fsetkeystar(byte[] bits) { int i,j; for (i=0;i<28;i++) C[0][i]=bits[pc_1_cp[i]-1]; for (i=0;i<28;i++) D[0][i]=bits[pc_1_dp[i]-1]; for (j=0;j<16;j++) { FLS(C[j],C[j+1],ls_countp[j]); FLS(D[j],D[j+1],ls_countp[j]); Fson(C[j+1],D[j+1],K[j+1]); } } private void Fiip(byte[] text,byte[] ll,byte[] rr) { int i,j; byte[] buffer=new byte[64]; byte[] tmp=new byte[64]; Fexpand0(text,buffer); for (i=0;i<32;i++) ll[i]=buffer[iip_tab_p[i]-1]; for (i=0;i<32;i++) rr[i]=buffer[iip_tab_p[i+32]-1]; } private void Fs_box(byte[] aa,byte[] bb) { int i,j,k,m; int y,z; byte[] ss=new byte[8]; m=0; for (i=0;i<8;i++) { j=6*i; y=b2iu(aa[j])*2+b2iu(aa[j+5]); z=b2iu(aa[j+1])*8+b2iu(aa[j+2])*4+b2iu(aa[j+3])*2+b2iu(aa[j+4]); ss[i]=iu2b(ccom_SSS_p[i][y][z]); y=3; for (k=0;k<4;k++) { bb[m++]=iu2b((b2iu(ss[i])>>>y)&1); y--; } } } private void FF(int n,byte[] ll,byte[] rr,byte[] LL,byte[] RR) { int i,j; byte[] buffer=new byte[64],tmp=new byte[64]; for (i=0;i<48;i++) buffer[i]=rr[e_r_p[i]-1]; for (i=0;i<48;i++) buffer[i]=iu2b((b2iu(buffer[i])+b2iu(K[n][i]))&1); Fs_box(buffer,tmp); for (i=0;i<32;i++) buffer[i]=tmp[local_PP[i]-1]; for (i=0;i<32;i++) RR[i]=iu2b((b2iu(buffer[i])+b2iu(ll[i]))&1); for (i=0;i<32;i++) LL[i]=rr[i]; } private void _Fiip(byte[] text,byte[] ll,byte[] rr) { int i,j; byte[] tmp=new byte[64]; for (i=0;i<32;i++) tmp[i]=ll[i]; for (i=32;i<64;i++) tmp[i]=rr[i-32]; for (i=0;i<64;i++) text[i]=tmp[_iip_tab_p[i]-1]; } private void Fcompress016(byte[] out,byte[] in) { int times; int i,j; for (i=0;i<16;i++) { times=3; in[i]='0'; for (j=0;j<4;j++) { in[i]=iu2b(b2iu(in[i])+(b2iu(out[i*16+j])<<times)); times--; } } } void Fcompress0(byte[] out,byte[] in) { int times; int i,j; for (i=0;i<8;i++) { times=7; in[i]=0; for (j=0;j<8;j++) { in[i]=iu2b(b2iu(in[i])+(b2iu(out[i*8+j])<<times)); times--; } } } private void Fencrypt0(byte[] text,byte[] mtext) { byte[] ll=new byte[64],rr=new byte[64],LL=new byte[64],RR=new byte[64]; byte[] tmp=new byte[64]; int i,j; Fiip(text,ll,rr); for (i=1;i<17;i++) { FF(i,ll,rr,LL,RR); for (j=0;j<32;j++) { ll[j]=LL[j]; rr[j]=RR[j]; } } _Fiip(tmp,rr,ll); Fcompress0(tmp,mtext); } private void FDES(byte[] key,byte[] text,byte[] mtext) { byte[] tmp=new byte[64]; Fexpand0(key,tmp); Fsetkeystar(tmp); Fencrypt0(text,mtext); } /*加密*/ public int ENCRYPT(byte[] key, byte[] s,byte[] d,int len ) { int i,j; byte[] cData=new byte[8]; byte[] cEncryptData=new byte[8]; for (i=0;i<len;i+=8) { if ((i+8)>len) { desMemcpy(cData,s,0,i,len-i); for (j = len-i; j < 8; j++) cData[j] = 0; } else desMemcpy(cData,s,0,i,8); FDES(key,cData,cEncryptData); desMemcpy(d,cEncryptData,i,0,8); } return i; } private void Fdiscrypt0(byte[] mtext,byte[] text) { byte[] ll=new byte[64],rr=new byte[64],LL=new byte[64],RR=new byte[64]; byte[] tmp=new byte[64]; int i,j; Fiip(mtext,ll,rr); for (i=16;i>0;i--) { FF(i,ll,rr,LL,RR); for (j=0;j<32;j++) { ll[j]=LL[j]; rr[j]=RR[j]; } } _Fiip(tmp,rr,ll); Fcompress0(tmp,text); } /***************************************************************************** * function: DES * parameter: u_char * key ; key for encrypt * u_char * mtext ; encipher data * u_char * text ; plain data * return: none *****************************************************************************/ private void _FDES(byte[] key,byte[] mtext,byte[] text) { byte[] tmp=new byte[64]; Fexpand0(key,tmp); Fsetkeystar(tmp); Fdiscrypt0(mtext,text); } /*解密*/ public int DECRYPT(byte[] key, byte[] s,byte[] d,int len ) { int i; byte[] cData=new byte[8]; byte[] cEncryptData=new byte[8]; for(i=0;i<len;i+=8) { desMemcpy(cEncryptData,d,0,i,8); _FDES(key,cEncryptData,cData); desMemcpy(s,cData,i,0,8); } return i; } public static byte[] hexStr2ByteArr(String strIn) { byte[] arrB = strIn.getBytes(); int iLen = arrB.length; //两个字符表示一个字节,所以字节数组长度是字符串长度除以2 byte[] arrOut = new byte[iLen / 2]; for (int i = 0; i < iLen; i = i + 2) { String strTmp = new String(arrB, i, 2); arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16); } return arrOut; } }
3DES简介
密码学中,3DES(或称为Triple DES)是三重数据加密算法(TDEA,Triple Data Encryption Algorithm)块密码的通称。它相当于是对每个数据块应用三次DES加密算法。由于计算机运算能力的增强,原版DES密码的密钥长度变得容易被暴力破解;3DES即是设计用来提供一种相对简单的方法,即通过增加DES的密钥长度来避免类似的攻击,而不是设计一种全新的块密码算法。
package com.star.sms.business.provision.send.util.encrypt; import java.security.Key; import java.security.NoSuchAlgorithmException; import java.security.SecureRandom; import java.security.Security; import javax.crypto.Cipher; import javax.crypto.KeyGenerator; import javax.crypto.SecretKey; import javax.crypto.spec.SecretKeySpec; import com.sun.crypto.provider.SunJCE; /** * @author xuefc * @version 1.0 */ public class Des_3DesUtils { // ----------------------------3DES---------------------------- /** * 生成3DES密钥. * * @param key_byte * seed key * @throws Exception * @return javax.crypto.SecretKey Generated DES key */ public static SecretKey genTripleDesKey(byte[] byteKey) { if (byteKey == null) { return null; } return new SecretKeySpec(byteKey, "DESede"); } public static SecretKey genTripleDesKey(String strKey) { if (strKey == null) { return null; } return genTripleDesKey(strKey.getBytes()); } /** * 3DES 解密(byte[]). * * @param key * SecretKey * @param crypt * byte[] * @throws Exception * @return byte[] */ public static byte[] tripleDesDecrypt(SecretKey key, byte[] data) { try { Cipher cipher = Cipher.getInstance("DESede/ECB/NoPadding"); cipher.init(Cipher.DECRYPT_MODE, key); return cipher.doFinal(data); } catch (Exception e) { throw new EncryptException(e); } } /** * 3DES 解密. * 因为3DES是对称加密算法,key是24位,当只有16位时,后8位取key的前8位 * @param key * SecretKey * @param crypt * byte[] * @throws Exception * @return byte[] */ public static byte[] tripleDesDecrypt(byte[] byteKey, byte[] data) { byte[] keys = null; if (byteKey.length == 16) { keys = new byte[24]; System.arraycopy(byteKey, 0,keys , 0, 16); System.arraycopy(byteKey, 0,keys , 16, 8); } else { keys = byteKey; } return tripleDesDecrypt(genTripleDesKey(keys), data); } /** * 3DES加密(byte[]). * * @param key * SecretKey * @param src * byte[] * @throws Exception * @return byte[] */ public static byte[] tripleDesEncrypt(SecretKey key, byte[] data) { try { Cipher cipher = Cipher.getInstance("DESede/ECB/NoPadding"); cipher.init(Cipher.ENCRYPT_MODE, key); return cipher.doFinal(data); } catch (Exception e) { throw new EncryptException(e); } } /** * 3DES加密(byte[]). * 因为3DES是对称加密算法,key是24位,当只有16位时,后8位取key的前8位 * @param key * SecretKey * @param src * byte[] * @throws Exception * @return byte[] */ public static byte[] tripleDesEncrypt(byte[] byteKey, byte[] data) { byte[] keys = null; if (byteKey.length == 16) { keys = new byte[24]; System.arraycopy(byteKey, 0,keys , 0, 16); System.arraycopy(byteKey, 0,keys , 16, 8); } else { keys = byteKey; } return tripleDesEncrypt(genTripleDesKey(keys), data); } // ----------------------------DES---------------------------- /** * 获得DES加密的密钥。需要JCE的支持,如果jdk版本低于1.4,则需要 安装jce-1_2_2才能正常使用。 * * @return Key 返回对称密钥 * @throws java.security.NoSuchAlgorithmException * @see util.EncryptUtil 其中包括加密和解密的方法 */ public static Key getDesKey(byte[] key) { if (key == null) { return null; } try { Security.insertProviderAt(new SunJCE(), 1); KeyGenerator generator = KeyGenerator.getInstance("DES"); generator.init(new SecureRandom(key)); return generator.generateKey(); } catch (NoSuchAlgorithmException e) { throw new EncryptException(e); } } public static Key getDesKey(String key) { if (key == null) { return null; } return getDesKey(key.getBytes()); } /** * DES加密 * * @param key * 密钥 * @param data * 需要加密的数据 * @return byte[] 加密后的数据 * @throws util.EncryptException */ public static byte[] desEncrypt(byte[] byteKey, byte[] data) { // return desEncrypt(getDesKey(byteKey), data); try { byte[] encryptData = new byte[data.length]; DesEncrypt de = new DesEncrypt(); de.ENCRYPT(byteKey, data, encryptData, data.length); return encryptData; } catch (Exception e) { throw new EncryptException(e); } } /** * DES解密 * * @param key * 密钥 * @param raw * 待解密的数据 * @return byte[] 解密后的数据 * @throws util.EncryptException */ public static byte[] desDecrypt(byte[] byteKey, byte[] data) { // return desDecrypt(getDesKey(byteKey), data); try { byte[] plainData = new byte[data.length]; DesEncrypt de = new DesEncrypt(); de.DECRYPT(byteKey, plainData, data, data.length); return plainData; } catch (Exception e) { throw new EncryptException(e); } } public static String getHexStr(byte[] data) { if (data == null) { return ""; } StringBuffer str = new StringBuffer(); for (byte b : data) { String temp = Integer.toHexString(b & 0xFF); // str.append("0x"); if (temp.length() == 1) { str.append("0" + temp); } else { str.append(temp); } str.append(","); } return str.substring(0,str.length()-1).toString(); } } class EncryptException extends RuntimeException { private static final long serialVersionUID = 1L; public EncryptException(String msg) { } public EncryptException(Throwable e) { super(e); } }