DES加密軟件 des加密解密工具



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DES加密軟件 des加密解密工具

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??DES算法簡介
DES 算法
??DES算法為密碼體制中的對稱密碼體制,又被稱為美國數據加密標準,是1972年美國IBM公司研制的對稱密碼體制加密算法 。明文按64位進行分組,密鑰長64位,密鑰事實上是56位參與DES運算(第8、16、24、32、40、48、56、64位是校驗位,使得每個密鑰都有奇數個1)分組后的明文組和56位的密鑰按位替代或交換的方法形成密文組的加密方法 。
??DES算法具有極高安全性,除了用窮舉搜索法對DES算法進行攻擊外,還沒有發現更有效的辦法 。而56位長的密鑰的窮舉空間為2^56,這意味著如果一臺計算機的速度是每一秒鐘檢測一百萬個密鑰,則它搜索完全部密鑰就需要將近2285年的時間,可見,這是難以實現的 。然而,這并不等于說DES是不可破解的 。而實際上,隨著硬件技術和Internet的發展,其破解的可能性越來越大,而且,所需要的時間越來越少 。使用經過特殊設計的硬件并行處理要幾個小時 。
??為了克服DES密鑰空間小的缺陷,人們又提出了三重DES的變形方式 。
??Maven 依賴
??工具類對于加密后使用Base64進行編碼,所以需要依賴Apache Commons Codec 。
<dependency><groupId>commons-codec</groupId><artifactId>commons-codec</artifactId><version>1.9</version></dependency><dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>1.2.17</version></dependency>??工具類實現
??DESUtil提供了針對文本內容、字節數組內容的加解密實現,DESUtil工具類可以直接復制使用,代碼如下:
package com.arhorchin.securitit.enordecryption.des;import java.security.Key;import javax.crypto.Cipher;import javax.crypto.SecretKeyFactory;import javax.crypto.spec.DESKeySpec;import javax.crypto.spec.IvParameterSpec;import org.apache.commons.codec.binary.Base64;import org.apache.log4j.Logger;/** * @author Securitit. * @note DES加密算法實現. */public class DESUtil {/*** logger.*/private static Logger logger = Logger.getLogger(DESUtil.class);/*** 數據編碼.*/private static final String CHARSET_UTF8 = "UTF-8";/*** 算法編號.*/public static final String DES_NAME = "DES";/*** CBC模式串.*/public static final String DES_NAME_ECB = "DES/CBC/PKCS5Padding";/*** 初始向量.*/public static final byte[] DES_KEY_IV = { 1, 2, 3, 4, 5, 6, 7, 8 };/*** 根據密碼生成Key.要求:密碼長度是8的倍數.* @param desKeyPwd 密碼字符串.* @return DES密鑰.* @throws Exception 可能異常.*/public static String generateDesKey(String desKeyPwd) throws Exception {DESKeySpec desKeySpec = null;SecretKeyFactory keyFactory = null;byte[] keyBytes = null;desKeySpec = new DESKeySpec(desKeyPwd.getBytes(CHARSET_UTF8));keyFactory = SecretKeyFactory.getInstance(DES_NAME);keyBytes = keyFactory.generateSecret(desKeySpec).getEncoded();return Base64.encodeBase64String(keyBytes);}/*** 對文本內容進行加密.* @param plainText 待加密明文內容.* @param desKey DES密鑰.* @return 加密的密文.*/public static String encodeText(String plainText, String desKey) throws Exception {byte[] desKeyBytes = null;byte[] plainBytes = null;byte[] cipherBytes = null;try {desKeyBytes = Base64.decodeBase64(desKey);plainBytes = plainText.getBytes(CHARSET_UTF8);cipherBytes = encodeByCbc(plainBytes, desKeyBytes, DES_KEY_IV);return Base64.encodeBase64String(cipherBytes);} catch (Exception ex) {logger.error("DESUtil.encodeText.", ex);return "";}}/*** 對文本密文進行解密.* @param cipherText 待解密密文.* @param desKey DES密鑰.* @return 解密的明文.*/public static String decodeText(String cipherText, String desKey) throws Exception {byte[] desKeyBytes = null;byte[] cipherBytes = null;byte[] plainBytes = null;try {desKeyBytes = Base64.decodeBase64(desKey);cipherBytes = Base64.decodeBase64(cipherText);plainBytes = decodeByCbc(cipherBytes, desKeyBytes, DES_KEY_IV);return new String(plainBytes, CHARSET_UTF8);} catch (Exception ex) {logger.error("DESUtil.decodeText.", ex);return "";}}/*** 對字節數組內容進行加密.* @param plainText 待加密明文內容.* @param dseKey DES密鑰.* @return 加密的密文.*/public static byte[] encodeBytes(byte[] plainBytes, String desKey) throws Exception {byte[] desKeyBytes = null;byte[] cipherBytes = null;try {desKeyBytes = Base64.decodeBase64(desKey);cipherBytes = encodeByCbc(plainBytes, desKeyBytes, DES_KEY_IV);return cipherBytes;} catch (Exception ex) {logger.error("DESUtil.encodeBytes.", ex);return new byte[0];}}/*** 對字節數組密文進行解密.* @param cipherText 待解密密文.* @param desKey DES密鑰.* @return 解密的明文.*/public static byte[] decodeBytes(byte[] cipherBytes, String desKey) throws Exception {byte[] desKeyBytes = null;byte[] plainBytes = null;try {desKeyBytes = Base64.decodeBase64(desKey);plainBytes = decodeByCbc(cipherBytes, desKeyBytes, DES_KEY_IV);return plainBytes;} catch (Exception ex) {logger.error("DESUtil.decodeBytes.", ex);return new byte[0];}}/*** DES算法使用CBC模式進行加密.* @param plainBytes 原文內容.* @param desKey DES密鑰.* @param keyIv DES初始向量.* @return 加密后的內容.* @throws Exception .*/public static byte[] encodeByCbc(byte[] plainBytes, byte[] desKey, byte[] keyIv) throws Exception {Key deskey = null;DESKeySpec desSpec = null;SecretKeyFactory keyFactory = null;Cipher cipher = null;IvParameterSpec ivSpec = null;byte[] cipherOut = null;desSpec = new DESKeySpec(desKey);keyFactory = SecretKeyFactory.getInstance(DES_NAME);deskey = keyFactory.generateSecret(desSpec);cipher = Cipher.getInstance(DES_NAME_ECB);ivSpec = new IvParameterSpec(keyIv);cipher.init(Cipher.ENCRYPT_MODE, deskey, ivSpec);cipherOut = cipher.doFinal(plainBytes);return cipherOut;}/*** DES算法使用CBC模式進行解密.* @param plainBytes 密文內容.* @param desKey DES密鑰.* @param keyIv DES初始向量.* @return 解密后的內容.* @throws Exception .*/public static byte[] decodeByCbc(byte[] plainBytes, byte[] desKey, byte[] keyIv) throws Exception {Key deskey = null;DESKeySpec desSpec = null;SecretKeyFactory keyFactory = null;Cipher cipher = null;IvParameterSpec ivSpec = null;byte[] cipherOut = null;desSpec = new DESKeySpec(desKey);keyFactory = SecretKeyFactory.getInstance(DES_NAME);deskey = keyFactory.generateSecret(desSpec);cipher = Cipher.getInstance(DES_NAME_ECB);ivSpec = new IvParameterSpec(keyIv);cipher.init(Cipher.DECRYPT_MODE, deskey, ivSpec);cipherOut = cipher.doFinal(plainBytes);return cipherOut;}}【DES加密軟件 des加密解密工具】??工具類測試
package com.arhorchin.securitit.enordecryption.des;import java.util.Arrays;/** * @author Securitit. * @note DESUtil測試類. */public class DESUtilTester {public static void main(String[] args) throws Exception {String desKeyPwd = "1234567887654321";String desKey = null;String plainText = "This is 一段明文內容!";String cipherText = null;System.out.println("----------------------- 獲取DES秘鑰 -------------------------");desKey = DESUtil.generateDesKey(desKeyPwd);System.out.println("秘鑰:" + desKey);System.out.println();// 文本加解密測試.System.out.println("----------------------- 文本加解密測試 -------------------------");System.out.println("明文:" + plainText);cipherText = DESUtil.encodeText(plainText, desKey);System.out.println("密文:" + cipherText);plainText = DESUtil.decodeText(cipherText, desKey);System.out.println("解密明文:" + plainText);System.out.println();System.out.println("----------------------- 字節數組加解密測試 -------------------------");byte[] plainBytes = plainText.getBytes("UTF-8");byte[] cipherBytes = null;System.out.println("明文:" + Arrays.toString(plainBytes));cipherBytes = DESUtil.encodeBytes(plainBytes, desKey);System.out.println("密文:" + Arrays.toString(cipherBytes));plainBytes = DESUtil.decodeBytes(cipherBytes, desKey);System.out.println("解密明文:" + Arrays.toString(plainBytes));System.out.println();}}??控制臺輸出
??查看Console中的控制臺內容,明文和解密后明文對比,可以確認DESUtil可以正常工作,控制臺如下圖:
----------------------- 獲取DES秘鑰 -------------------------秘鑰:MTIyNDQ3Nzg=----------------------- 文本加解密測試 -------------------------明文:This is 一段明文內容!密文:2guHzIWpad0klMjyRZERLW83acN0AM0F19NZ18NF214=解密明文:This is 一段明文內容!----------------------- 字節數組加解密測試 -------------------------明文:[84, 104, 105, 115, 32, 105, 115, 32, -28, -72, -128, -26, -82, -75, -26, -104, -114, -26, -106, -121, -27, -122, -123, -27, -82, -71, -17, -68, -127]密文:[-38, 11, -121, -52, -123, -87, 105, -35, 36, -108, -56, -14, 69, -111, 17, 45, 111, 55, 105, -61, 116, 0, -51, 5, -41, -45, 89, -41, -61, 69, -37, 94]解密明文:[84, 104, 105, 115, 32, 105, 115, 32, -28, -72, -128, -26, -82, -75, -26, -104, -114, -26, -106, -121, -27, -122, -123, -27, -82, -71, -17, -68, -127]??總結
??現代密碼學應用中,DES的身影已越來越少見,隨著硬件和互聯網的發展,DES在安全性方面的劣勢變得尤為明顯 。在DES之后,逐漸出現了用于過渡的3DES以及新一代密碼算法AES,3DES是為了使得DES更加難以破解,使用三次DES加解密疊加得到的密碼算法 。而AES是作為下一代對稱密碼學算法,使用完全不同的算法進行了實現 。在實際應用中,可以根據個人所需,選擇合適的算法進行應用 。