Geçersiz AES anahtar uzunluğu nasıl düzeltilir? Tutulma üzerinde web tabanlı <strong>metin şifreleme ve şifre çözme</strong> proje üzerinde çalışıyorum

Question

(Struts aşağıdaki 2)

Ben şifre ve ben Geçersiz AES Anahtar Uzunluğu hatası alıyorum düz metin girmek zaman

.

Servis Sınıfı (SymAES.java)

package com.anoncrypt.services; 

import java.security.Key; 
import javax.crypto.Cipher; 
import javax.crypto.spec.SecretKeySpec; 

import sun.misc.BASE64Decoder; 
import sun.misc.BASE64Encoder; 

public class SymAES 
{ 
    private static final String ALGORITHM = "AES"; 
    private static byte[] keyValue= new byte[] { 'T', 'h', 'i', 's', 'I', 's', 'A', 'S', 'e', 'c', 'r', 'e', 't', 'K', 'e', 'y' }; 

    public String encode(String valueToEnc) throws Exception { 
     System.out.println("The Key byte value"+keyValue); 

     Key key = generateKey(); 
     Cipher c = Cipher.getInstance(ALGORITHM); 
     c.init(Cipher.ENCRYPT_MODE, key); 
     byte[] encValue = c.doFinal(valueToEnc.getBytes()); 
     String encryptedValue = new BASE64Encoder().encode(encValue); 
     return encryptedValue; 
    } 

    public String decode(String encryptedValue) throws Exception { 
     Key key = generateKey(); 
     Cipher c = Cipher.getInstance(ALGORITHM); 
     c.init(Cipher.DECRYPT_MODE, key); 
     byte[] decordedValue = new BASE64Decoder().decodeBuffer(encryptedValue); 
     byte[] decValue = c.doFinal(decordedValue); 
     String decryptedValue = new String(decValue); 
     return decryptedValue; 
    } 

    private static Key generateKey() throws Exception { 
     //System.out.println("passs value"+pass); 

     System.out.println("The Key byte value instde genkey"+keyValue); 
     Key key = new SecretKeySpec(keyValue, ALGORITHM); 
     return key; 
    } 

    public void start(String passcode)throws Exception 
    { 
     keyValue = passcode.getBytes(); 
     System.out.println("passcode"+passcode);  
     System.out.println("The Key byte value inside start"+keyValue); 
    } 
} 

İşte

---

Eylem Sınıfı (SymEncrypt.java) 'dir

package com.anoncrypt.actions; 

import com.anoncrypt.services.SymAES; 

public class SymEncrypt { 
    private String encrypt; 
    private String encrypted; 
    private String password; 

    boolean TEMP; 

    public String execute() throws Exception { 
     SymAES ob=new SymAES(); 
     ob.start(getPassword()); 

     setEncrypted(ob.encode(getEncrypt())); 
     System.out.println("into action class "+getEncrypted()); 

     if(getEncrypted().equals(null)) 
      return "error"; 
     else 
      return "success"; 
    } 

    public String getEncrypted() { 
     return encrypted; 
    } 

    public void setEncrypted(String encrypted) { 
     this.encrypted = encrypted; 
    } 

    public String getEncrypt() { 
     return encrypt; 
    } 

    public void setEncrypt(String encrypt) { 
     this.encrypt = encrypt; 
    } 

    public String getPassword() { 
     return password; 
    } 

    public void setPassword(String password) { 
     this.password = password; 
    } 
} 

Ve bu hata

olduğunu

java.security.InvalidKeyException: Invalid AES key length: 6 bytes 
    com.sun.crypto.provider.AESCrypt.init(AESCrypt.java:87) 
    com.sun.crypto.provider.ElectronicCodeBook.init(ElectronicCodeBook.java:93) 
    com.sun.crypto.provider.CipherCore.init(CipherCore.java:582) 
    com.sun.crypto.provider.CipherCore.init(CipherCore.java:458) 
    com.sun.crypto.provider.AESCipher.engineInit(AESCipher.java:307) 
    javax.crypto.Cipher.implInit(Cipher.java:797) 
    javax.crypto.Cipher.chooseProvider(Cipher.java:859) 
    javax.crypto.Cipher.init(Cipher.java:1229) 
    javax.crypto.Cipher.init(Cipher.java:1166) 
    com.anoncrypt.services.SymAES.encode(SymAES.java:35) 
    com.anoncrypt.actions.SymEncrypt.execute(SymEncrypt.java:24) 
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) 
    sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) 
    java.lang.reflect.Method.invoke(Unknown Source) 
    ognl.OgnlRuntime.invokeMethod(OgnlRuntime.java:870) 
    ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1293) 
    ognl.ObjectMethodAccessor.callMethod(ObjectMethodAccessor.java:68) 
    com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethodWithDebugInfo(XWorkMethodAccessor.java:117) 
    com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethod(XWorkMethodAccessor.java:108) 
    ognl.OgnlRuntime.callMethod(OgnlRuntime.java:1369) 
    ognl.ASTMethod.getValueBody(ASTMethod.java:90) 
    ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:212) 
    ognl.SimpleNode.getValue(SimpleNode.java:258) 
    ognl.Ognl.getValue(Ognl.java:494) 
    ognl.Ognl.getValue(Ognl.java:458) 
    com.opensymphony.xwork2.ognl.OgnlUtil$2.execute(OgnlUtil.java:309) 
    com.opensymphony.xwork2.ognl.OgnlUtil.compileAndExecute(OgnlUtil.java:340) 
    com.opensymphony.xwork2.ognl.OgnlUtil.getValue(OgnlUtil.java:307) 
    com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:423) 
    com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:287) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:250) 
    org.apache.struts2.interceptor.DeprecationInterceptor.intercept(DeprecationInterceptor.java:41) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:167) 
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265) 
    org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:76) 
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) 
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) 
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:191) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:73) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.interceptor.DateTextFieldInterceptor.intercept(DateTextFieldInterceptor.java:125) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:91) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:253) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171) 
    com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:139) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:193) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:189) 
    com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:244) 
    org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54) 
    org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:564) 
    org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:81) 
    org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99) 

Answer 1

AES yalnızca 16, 24 veya 32 baytlık anahtar boyutlarını destekler. Ya tam olarak bu tutarı sağlamanız ya da anahtarı yazdığınızdan türetmeniz gerekir.

Anahtarın bir paroladan alınmasının farklı yolları vardır. Java, böyle bir amaç için bir PBKDF2 uygulaması sağlar.

ben tam bir resmini boyamak için erickson en answer kullanılan (şifre çözme benzer olduğundan, sadece şifrelemeyi ancak şifreli bölme içerir): akılda tutulması gereken

SecureRandom random = new SecureRandom(); 
byte[] salt = new byte[16]; 
random.nextBytes(salt); 

KeySpec spec = new PBEKeySpec("password".toCharArray(), salt, 65536, 256); // AES-256 
SecretKeyFactory f = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1"); 
byte[] key = f.generateSecret(spec).getEncoded(); 

byte[] ivBytes = new byte[16]; 
random.nextBytes(ivBytes); 
IvParameterSpec iv = new IvParameterSpec(ivBytes); 

Cipher c = Cipher.getInstance("AES/CBC/PKCS5Padding"); 
c.init(Cipher.ENCRYPT_MODE, key, iv); 
byte[] encValue = c.doFinal(valueToEnc.getBytes()); 

byte[] finalCiphertext = new byte[encValue.length+2*16]; 
System.arraycopy(ivBytes, 0, finalCiphertext, 0, 16); 
System.arraycopy(salt, 0, finalCiphertext, 16, 16); 
System.arraycopy(encValue, 0, finalCiphertext, 32, encValue.length); 

return finalCiphertext; 

---

Diğer şeyler:

• Her zaman tam nitelikli bir Cipher adı kullanın. Böyle bir durumda AES uygun değildir, çünkü farklı JVMs/JCE sağlayıcıları çalışma modu ve dolgu için farklı varsayılan değerleri kullanabilir. AES/CBC/PKCS5Padding kullanın. ECB modunu kullanmayın çünkü semantik olarak güvenli değildir.
• ECB modunu kullanmıyorsanız, IV ile birlikte şifreli metin göndermeniz gerekir. Bu genellikle IV'i şifreli metin bayt dizisine önekleyerek yapılır. IV sizin için otomatik olarak oluşturulur ve cipherInstance.getIV()'dan edinebilirsiniz.
• Bir şey gönderdiğinizde, yol boyunca değiştirilmediğinden emin olmanız gerekir. MAC ile doğru bir şifreleme uygulamak zordur. CCM veya GCM gibi kimliği doğrulanmış bir mod kullanmanızı öneririm. Ben aynı sorunu bakıyordu

Answer 2

sonra benim anahtar 16 byte yaptı ve artık düzgün çalışıyor. Anahtarınızı tam 16 baytlık olarak oluşturun. Kesinlikle işe yarayacak.

Answer 3

Anahtar uzunluğu sınırı doğrulayabilirsiniz:

int maxKeyLen = Cipher.getMaxAllowedKeyLength("AES"); 
System.out.println("MaxAllowedKeyLength=[" + maxKeyLen + "].");