网络安全实验报告书

网络安全实验报告 姓名： 白晨 班级： 软件22指导老师： 田暄提交日期： 2015-12-10目录1 加解密与认证 21.1 实验环境 21.2 源代码与注释 21.3 运行结果与分析 72 RC4流密码加密实现 82.1 实验环境 82.2 源代码与注释 82.3 运行结果与分析 103 大于3人实现证书生成、签发、通信 113.1 实验环境 113.2 实验过程与分析 11

加解密与认证要求：结合所提供密码学开发库或利用Java，vc自带密码学开发库完成如下要求1）设计实现消息的机密性，完整性与可鉴别，认证要求。2）报告中要有思路分析，设计流程与关键代码。每步变换后的结果3）要求结合个人信息进行，如消息中应包含个人学号，姓名等4）应使用到消息分组，不能太短实验环境语言 :JavaIDE :Eclipse绿色版源代码与注释importjava.security.InvalidKeyException;importjava.security.KeyPair;importjava.security.KeyPairGenerator;importjava.security.MessageDigest;importjava.security.NoSuchAlgorithmException;importjava.security.PrivateKey;importjava.security.PublicKey;importjava.security.SecureRandom;importjava.security.Signature;importjava.security.SignatureException;importjavax.crypto.BadPaddingException;importjavax.crypto.Cipher;importjavax.crypto.IllegalBlockSizeException;importjavax.crypto.KeyGenerator;importjavax.crypto.NoSuchPaddingException;importjavax.crypto.SecretKey;publicclassEncryptionAndDecryption{ privatestaticfinalintGROUP_SIZE=128; privatestaticfinalintGROUP_MSG_SIZE=28; //28bytespergroup privatestaticfinalintGROUP_HEAD_SIZE=24; privatestaticfinalintDIGEST_SIZE=20; privatestaticfinalintOFFSET_GROUP_SIZE=20; privatestaticfinalintOFFSET_CUR_GROUP=22; privatestaticfinalintOFFSET_MSG_START=24; privatestaticfinalintOFFSET_SIGN_SIZE=77; privatestaticfinalintOFFSET_SIGN_START=78; //Storeplaintext /*Attributes***********************************************/ privateStringmMsg; privatebyte[][]mCipers; privateMessageDigestmMsgDigest; privateKeyPairGeneratormKeyPairGenerator; privatePublicKeymPublicKey; privatePrivateKeymPrivateKey; privateSignaturemSignature; privateKeyGeneratormKeyGenerator; privateSecretKeymDesKey; privateCiphermCipher;/*EncryptionandDecryption*************************************/ publicEncryptionAndDecryption(){ try{ mMsgDigest=MessageDigest.getInstance("SHA-1");//UseSHA-1togetMsgdigest mKeyPairGenerator=KeyPairGenerator.getInstance("DSA");//SignatureAlgorithmisDSA SecureRandomsecrand=newSecureRandom(); //Random secrand.setSeed("BC".getBytes()); //Usebytesoftexttogenerateaseed mKeyPairGenerator.initialize(512,secrand); //Generatethekeypair KeyPairkeys=mKeyPairGenerator.generateKeyPair(); //Getkeys mPublicKey=keys.getPublic(); //Kpu mPrivateKey=keys.getPrivate(); //Kpr mSignature=Signature.getInstance("DSA"); mKeyGenerator=KeyGenerator.getInstance("DES"); //EncryptionAlgorithm mDesKey=mKeyGenerator.generateKey(); //DesKey mCipher=Cipher.getInstance("DES"); //Cipher }catch(NoSuchAlgorithmExceptione){ e.printStackTrace(); }catch(NoSuchPaddingExceptione){ e.printStackTrace(); } }/** *Splitthemessageintogroup(28bytespergroup) *@returnthemessagegroups */ privatebyte[][]splitMsg(){ finalintgroupSize=(mMsg.length()*2+1)/GROUP_MSG_SIZE+1; // System.out.println(groupSize); // System.out.println(mMsg.length()); byte[][]msgs=newbyte[groupSize][GROUP_MSG_SIZE]; byte[]msgBytes=mMsg.getBytes(); //System.out.println(msgBytes.length); for(inti=0;i<groupSize;i++){ for(intj=0;(j<GROUP_MSG_SIZE)&&(i*GROUP_MSG_SIZE+j<msgBytes.length);j++){ msgs[i][j]=msgBytes[i*GROUP_MSG_SIZE+j]; } } returnmsgs; }/** *Encryption *@returnCipher */ publicbyte[][]encrypt(){ //Splittheplaintextintogroup byte[][]plains=splitMsg(); //Plaintextgroup //System.out.println(plains.length); //System.out.println(mMsg.length()); print(plains); byte[][]groups=newbyte[plains.length][GROUP_SIZE]; //Messagebeforeencryption byte[][]ciphers=newbyte[plains.length][]; //Messageafterencryption //Encryptthegroups for(inti=0;i<groups.length;i++){ //Msgdigest mMsgDigest.update(plains[i].clone()); byte[]digest=mMsgDigest.digest(); //Signthemessage byte[]signs=newbyte[0]; try{ mSignature.initSign(mPrivateKey); mSignature.update(digest); signs=mSignature.sign(); }catch(SignatureExceptione){ e.printStackTrace(); }catch(InvalidKeyExceptione){ e.printStackTrace(); } //Filldigest for(intj=0;j<DIGEST_SIZE;j++){ groups[i][j]=digest[j]; } //Fillsignatureinformation groups[i][OFFSET_SIGN_SIZE]=(byte)signs.length; for(ints=0;s<signs.length;s++){ groups[i][OFFSET_SIGN_START+s]=signs[s]; } //Filltheinformationofcurrentgroup byte[]groupSize=toByteArray(plains.length,2); groups[i][OFFSET_GROUP_SIZE]=groupSize[0]; groups[i][OFFSET_GROUP_SIZE+1]=groupSize[1]; byte[]curGroup=toByteArray(i,2); groups[i][OFFSET_CUR_GROUP]=curGroup[0]; groups[i][OFFSET_CUR_GROUP+1]=curGroup[1]; //Fillthemessage for(intm=0;m<GROUP_MSG_SIZE&&m<plains[i].length;m++){ groups[i][OFFSET_MSG_START+m]=plains[i][m]; } //Printgroupsdatum System.out.println(""); for(byte[]temp:groups) { for(bytet:temp) { System.out.print(t+""); } System.out.println(); } //Encryptthemessage try{ mCipher.init(Cipher.ENCRYPT_MODE,mDesKey); ciphers[i]=mCipher.doFinal(groups[i]); }catch(IllegalBlockSizeExceptione){ e.printStackTrace(); }catch(BadPaddingExceptione){ e.printStackTrace(); }catch(InvalidKeyExceptione){ e.printStackTrace(); } } returnciphers; } privatebyte[]toByteArray(intvalue,inti){ //TODOAuto-generatedmethodstub byte[]b=newbyte[i]; b[1]=(byte)((value>>8)&0xFF); b[0]=(byte)(value&0xFF); returnb;} publicvoidsetMsg(Stringmsg){ mMsg=msg; } publicvoidsetCiphers(byte[][]ciphers){ mCipers=ciphers; }publicbyte[][]decrypt(){ byte[][]plains=newbyte[mCipers.length][GROUP_MSG_SIZE]; byte[][]groups=newbyte[mCipers.length][GROUP_SIZE]; for(inti=0;i<mCipers.length;i++){ //Decrytthemessagegroup byte[]plain=newbyte[GROUP_SIZE]; try{ mCipher.init(Cipher.DECRYPT_MODE,mDesKey); plain=mCipher.doFinal(mCipers[i]); }catch(InvalidKeyExceptione){ e.printStackTrace(); }catch(IllegalBlockSizeExceptione){ e.printStackTrace(); }catch(BadPaddingExceptione){ e.printStackTrace(); } //Verifythesignature byte[]signs=newbyte[plain[OFFSET_SIGN_SIZE]]; byte[]digest=newbyte[DIGEST_SIZE]; //Retrievethedigest for(intd=0;d<DIGEST_SIZE;d++){ digest[d]=plain[d]; } //Retrievethesigns for(ints=0;s<signs.length;s++){ signs[s]=plain[OFFSET_SIGN_START+s]; } try{ mSignature.initVerify(mPublicKey); mSignature.update(digest); if(mSignature.verify(signs)){ //Verifytheintegrity mMsgDigest.update(plain,OFFSET_MSG_START,GROUP_MSG_SIZE); if(MessageDigest.isEqual(digest,mMsgDigest.digest())){ //Getcurrentgroupoffset byte[]curGroup=newbyte[2]; curGroup[0]=plain[OFFSET_CUR_GROUP]; curGroup[1]=plain[OFFSET_CUR_GROUP+1]; intcurPos=toInt(curGroup); for(intj=0;j<GROUP_MSG_SIZE;j++){ plains[curPos][j]=plain[OFFSET_MSG_START+j]; } } }; }catch(SignatureExceptione){ e.printStackTrace(); }catch(InvalidKeyExceptione){ e.printStackTrace(); } } returnplains; } publicstaticvoidprint(byteplains[][]){ byte[]b=newbyte[(plains.length-1)*GROUP_MSG_SIZE+plains[plains.length-1].length]; intj=0; intk=0; for(inti=0;i<b.length;i++){ b[i]=plains[k][j]; j++; if(j==plains[0].length){ k++; j=0; } } System.out.println(newString(b)); } publicinttoInt(byte[]b){ intvalue; value=(int)((b[0]&0xFF) |((b[1]&0xFF)>>8) ); returnvalue; } publicstaticvoidmain(String[]args){ EncryptionAndDecryptiontest=newEncryptionAndDecryption(); test.setMsg("白晨-2121601027-软件学院-软件22-网安实验-加密与解密"); test.setCiphers(test.encrypt()); print(test.decrypt()); }}运行结果与分析实验所用加密算法为DES，签名算法为：DSA，消息摘要的生成用的为SHA-1，分组为28字节一组，内容结构为：摘要+分组信息+消息+签名长度+签名由于加密是对每一组进行加密的。在组中先填充消息摘要等消息。所以可以看到第二段(第一次加密Group1结束)中在密文第一个字节(-56)前有一段消息摘要等其他消息。解密后生成摘要与签名的摘要进行比对，没有问题。

RC4流密码加密实现实验环境语言 :JavaIDE :Eclipse绿色版源代码importjava.lang.Integer; classHomeWork{publicstaticStringMyRC4(StringaInput,StringaKey){int[]iS=newint[256]; byte[]iK=newbyte[256];for(inti=0;i<256;i++)iS[i]=i;intj=1;for(shorti=0;i<256;i++){iK[i]=(byte)aKey.charAt((i%aKey.length()));}j=0;for(inti=0;i<255;i++){j=(j+iS[i]+iK[i])%256;inttemp=iS[i];iS[i]=iS[j];iS[j]=temp;}inti=0;j=0;char[]iInputChar=aInput.toCharArray();char[]iOutputChar=newchar[iInputChar.length];for(shortx=0;x<iInputChar.length;x++){i=(i+1)%256;j=(j+iS[i])%256;inttemp=iS[i];iS[i]=iS[j];iS[j]=temp;intt=(iS[i]+(iS[j]%256))%256;intiY=iS[t];chariCY=(char)iY;iOutputChar[x]=(char)(iInputChar[x]^iCY);}returnnewString(iOutputChar);} publicstaticStringStrToBinstr(Stringstr){ char[]strChar=str.toCharArray(); Stringresult=""; for(inti=0;i<strChar.length;i++){ result+=Integer.toBinaryString(strChar[i])+""; }returnresult; } publicstaticvoidmain(String[]args) {StringinputStr="软件学院-白晨-软件222121601027";