InvalidKeyException : Illegal Key Size - Java code throwing exception for encryption class - how to fix?

Question

I've been trying to get some working Java code to use for encrypting Paypal buttons. This is no easy task! Even when I get some code, from Paypal, I'm faced with errors..ugh..

So here is what I have so far, that I think will work eventually.

I downloaded the Java.zip file from Paypal's website. Within it are two classes - ClientSide.java and ButtonEncryption.java

The Problem - I'm getting an InvalidKeyException : Illegal key size error.

Questions
1) How do I resolve this issue? 2) What line of code is throwing the error?

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C:\jakarta-tomcat\webapps\PlanB\WEB-INF\classes>java palmb.servlets.paypal.ButtonEncryption java.io.IOException: exception decrypting data - java.security.InvalidKeyException: Illegal key size         at org.bouncycastle.jce.provider.JDKPKCS12KeyStore.cryptData(Unknown Source)         at org.bouncycastle.jce.provider.JDKPKCS12KeyStore.engineLoad(Unknown Source)         at java.security.KeyStore.load(Unknown Source)         at palmb.servlets.paypal.ClientSide.getButtonEncryptionValue(ClientSide.java:63)         at palmb.servlets.paypal.ButtonEncryption.main(ButtonEncryption.java:81) 

ClientSide class

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package palmb.servlets.paypal;  import java.io.ByteArrayOutputStream; import java.io.FileInputStream; import java.io.IOException; import java.io.PrintWriter; import java.security.InvalidAlgorithmParameterException; import java.security.KeyStore; import java.security.KeyStoreException; import java.security.NoSuchAlgorithmException; import java.security.NoSuchProviderException; import java.security.PrivateKey; import java.security.UnrecoverableKeyException; import java.security.cert.CertStore; import java.security.cert.CertStoreException; import java.security.cert.CertificateException; import java.security.cert.CertificateFactory; import java.security.cert.CollectionCertStoreParameters; import java.security.cert.X509Certificate; import java.util.ArrayList; import java.util.Enumeration;  import org.bouncycastle.cms.CMSEnvelopedData; import org.bouncycastle.cms.CMSEnvelopedDataGenerator; import org.bouncycastle.cms.CMSException; import org.bouncycastle.cms.CMSProcessableByteArray; import org.bouncycastle.cms.CMSSignedData; import org.bouncycastle.cms.CMSSignedDataGenerator; import org.bouncycastle.openssl.PEMReader; import org.bouncycastle.util.encoders.Base64;  /**  */ public class ClientSide  {     private String  keyPath;     private String  certPath;     private String  paypalCertPath;     private String  keyPass;      public ClientSide( String keyPath, String certPath, String paypalCertPath, String keyPass )     {         this.keyPath = keyPath;         this.certPath = certPath;         this.paypalCertPath = paypalCertPath;         this.keyPass = keyPass;     }         public String getButtonEncryptionValue(String _data, String _privateKeyPath, String _certPath, String _payPalCertPath,                                             String _keyPass) throws IOException,CertificateException,KeyStoreException,                                             UnrecoverableKeyException,InvalidAlgorithmParameterException,NoSuchAlgorithmException,                                             NoSuchProviderException,CertStoreException,CMSException {         _data = _data.replace(',', '\n');         CertificateFactory cf = CertificateFactory.getInstance("X509", "BC");          // Read the Private Key         KeyStore ks = KeyStore.getInstance("PKCS12", "BC");         ks.load( new FileInputStream(_privateKeyPath), _keyPass.toCharArray() );          String keyAlias = null;         Enumeration aliases = ks.aliases();         while (aliases.hasMoreElements()) {             keyAlias = (String) aliases.nextElement();         }          PrivateKey privateKey = (PrivateKey) ks.getKey( keyAlias, _keyPass.toCharArray() );          // Read the Certificate         X509Certificate certificate = (X509Certificate) cf.generateCertificate( new FileInputStream(_certPath) );          // Read the PayPal Cert         X509Certificate payPalCert = (X509Certificate) cf.generateCertificate( new FileInputStream(_payPalCertPath) );          // Create the Data         byte[] data = _data.getBytes();          // Sign the Data with my signing only key pair         CMSSignedDataGenerator signedGenerator = new CMSSignedDataGenerator();          signedGenerator.addSigner( privateKey, certificate, CMSSignedDataGenerator.DIGEST_SHA1 );          ArrayList certList = new ArrayList();         certList.add(certificate);         CertStore certStore = CertStore.getInstance( "Collection", new CollectionCertStoreParameters(certList) );         signedGenerator.addCertificatesAndCRLs(certStore);          CMSProcessableByteArray cmsByteArray = new CMSProcessableByteArray(data);         ByteArrayOutputStream baos = new ByteArrayOutputStream();         cmsByteArray.write(baos);         System.out.println( "CMSProcessableByteArray contains [" + baos.toString() + "]" );          CMSSignedData signedData = signedGenerator.generate(cmsByteArray, true, "BC");          byte[] signed = signedData.getEncoded();          CMSEnvelopedDataGenerator envGenerator = new CMSEnvelopedDataGenerator();         envGenerator.addKeyTransRecipient(payPalCert);         CMSEnvelopedData envData = envGenerator.generate( new CMSProcessableByteArray(signed),                 CMSEnvelopedDataGenerator.DES_EDE3_CBC, "BC" );          byte[] pkcs7Bytes = envData.getEncoded();           return new String( DERtoPEM(pkcs7Bytes, "PKCS7") );      }      public static byte[] DERtoPEM(byte[] bytes, String headfoot)      {         ByteArrayOutputStream pemStream = new ByteArrayOutputStream();         PrintWriter writer = new PrintWriter(pemStream);          byte[] stringBytes = Base64.encode(bytes);          System.out.println("Converting " + stringBytes.length + " bytes");          String encoded = new String(stringBytes);          if (headfoot != null) {             writer.print("-----BEGIN " + headfoot + "-----\n");         }          // write 64 chars per line till done         int i = 0;         while ((i + 1) * 64 < encoded.length()) {             writer.print(encoded.substring(i * 64, (i + 1) * 64));             writer.print("\n");             i++;         }         if (encoded.length() % 64 != 0) {             writer.print(encoded.substring(i * 64)); // write remainder             writer.print("\n");         }         if (headfoot != null) {             writer.print("-----END " + headfoot + "-----\n");         }         writer.flush();         return pemStream.toByteArray();     }  } 

ButtonEncryption class

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package palmb.servlets.paypal;  //import com.paypal.crypto.sample.*;  import palmb.servlets.paypal.ClientSide;  import java.io.*; import java.security.InvalidAlgorithmParameterException; import java.security.KeyStoreException; import java.security.NoSuchAlgorithmException; import java.security.NoSuchProviderException; import java.security.Security; import java.security.UnrecoverableKeyException; import java.security.cert.CertStoreException; import java.security.cert.CertificateException; import org.bouncycastle.cms.CMSException;  /**  */ public class ButtonEncryption {       //path to public cert     private static String certPath = "C:/jakarta-tomcat/webapps/PlanB/Certs/public-cert.pem";      //path to private key in PKCS12 format     private static String keyPath = "C:/jakarta-tomcat/webapps/PlanB/Certs/my_pkcs12.p12";      //path to Paypal's public cert     private static String paypalCertPath = "C:/jakarta-tomcat/webapps/PlanB/Certs/paypal_cert_pem.txt";      //private key password     private static String keyPass = "password"; //will be replaced with actual password when compiled and executed      //the button command, properties/parameters     private static String cmdText = "cmd=_xclick\nbusiness=buyer@hotmail.com\nitem_name=vase\nitemprice=25.00";  //cmd=_xclick,business=sample@paypal.com,amount=1.00,currency_code=USD      //output file for form code     private static String output = "test.html";       public static void main(String[] args)      {         Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());            String stage = "sandbox";          try          {             ClientSide client_side = new ClientSide( keyPath, certPath, paypalCertPath, keyPass );              String result = client_side.getButtonEncryptionValue( cmdText, keyPath, certPath, paypalCertPath, keyPass );              File outputFile = new File( output );             if ( outputFile.exists() )                 outputFile.delete();              if ( result != null && result != "")             {                 try {                             OutputStream fout= new FileOutputStream( output );                     OutputStream bout= new BufferedOutputStream(fout);                     OutputStreamWriter out = new OutputStreamWriter(bout, "US-ASCII");                      out.write( "<form action=\"https://www." );                     out.write( stage );                     out.write( "paypal.com/cgi-bin/webscr\" method=\"post\">" );                       out.write( "<input type=\"hidden\" name=\"cmd\" value=\"_s-xclick\">" );  ;                     out.write( "<input type=\"image\" src=\"https://www." );                     out.write( stage );                     out.write( "paypal.com/en_US/i/btn/x-click-but23.gif\" border=\"0\" name=\"submit\" " );                     out.write( "alt=\"Make payments with PayPal - it's fast, free and secure!\">" );                     out.write( "<input type=\"hidden\" name=\"encrypted\" value=\"" );                     out.write( result );                     out.write( "\">" );                     out.write( "</form>");                      out.flush();  // Don't forget to flush!                     out.close();                   }                   catch (UnsupportedEncodingException e) {                     System.out.println(                      "This VM does not support the ASCII character set."                     );                   }                   catch (IOException e) {                     System.out.println(e.getMessage());                           }             }         }          catch (NoSuchAlgorithmException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (NoSuchProviderException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (IOException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (CMSException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (CertificateException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (KeyStoreException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (UnrecoverableKeyException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (InvalidAlgorithmParameterException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }          catch (CertStoreException e)          {             // TODO Auto-generated catch block             e.printStackTrace();         }     } } 

Edited : info about keys/certificates

I generated the Private Key and Public Certificate with OpenSSL via the following commands.
Private Key
openssl genrsa -out private-key.pem 1024
Public Certificate
openssl req -new -key private-key.pem -x509 -days 1095 -out public-cert.pem
Created PKCS12 File
openssl pkcs12 -export -in public-cert.pem -inkey private-key.pem -out my_pkcs12.p12

Additionally, I had to download the Paypal Public Certificate from the Paypal website.

Edited - adding compilation warnings - BouncyCastle

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C:\jakarta-tomcat\webapps\PlanB\WEB-INF\classes>javac .\palmb\servlets\paypal\ClientSide.java -Xlint .\palmb\servlets\paypal\ClientSide.java:85: warning: [deprecation] addSigner(java.security.PrivateKey,java.security.cert.X509Certificate,java.lang.String) in org.bouncycastle.cms.CMSSignedDataGenerator has been deprecated                 signedGenerator.addSigner( privateKey, certificate, CMSSignedDat aGenerator.DIGEST_SHA1 );                                ^ .\palmb\servlets\paypal\ClientSide.java:88: warning: [unchecked] unchecked call to add(E) as a member of the raw type java.util.ArrayList                 certList.add(certificate);                             ^ .\palmb\servlets\paypal\ClientSide.java:90: warning: [deprecation] addCertificatesAndCRLs(java.security.cert.CertStore) in org.bouncycastle.cms.CMSSignedGenerat or has been deprecated                 signedGenerator.addCertificatesAndCRLs(certStore);                                ^ .\palmb\servlets\paypal\ClientSide.java:97: warning: [deprecation] generate(org. bouncycastle.cms.CMSProcessable,boolean,java.lang.String) in org.bouncycastle.cm s.CMSSignedDataGenerator has been deprecated                 CMSSignedData signedData = signedGenerator.generate(cmsByteArray, true, "BC");                                                           ^ .\palmb\servlets\paypal\ClientSide.java:102: warning: [deprecation] addKeyTransR ecipient(java.security.cert.X509Certificate) in org.bouncycastle.cms.CMSEnvelope dGenerator has been deprecated                 envGenerator.addKeyTransRecipient(payPalCert);                             ^ .\palmb\servlets\paypal\ClientSide.java:103: warning: [deprecation] generate(org.bouncycastle.cms.CMSProcessable,java.lang.String,java.lang.String) in org.bouncycastle.cms.CMSEnvelopedDataGenerator has been deprecated                 CMSEnvelopedData envData = envGenerator.generate( new CMSProcess ableByteArray(signed),                                                        ^ 6 warnings 

JCE policy file installation steps

These are the steps I took to installing the JCE Unlimited Strength Policy files:
1) Went to Java JCE Download Page on Oracle.
2) Extracted files from zip.
3) Placed local_policy.jar and US_export_policy.jar files in C:\Java\jdk1.6.0_22\jre\lib\security folder.
Note: C:\Java\jdk1.6.0_22 is set as %JAVA_HOME%
4) Updated system classpath to include location of jars.
Note: There are other files, that came with the JDK 1.6 within the security folder, including : java.policy, java.security, javaws.policy, trusted.libraries - but those probably have nothing to do with the JCE files, right?

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Edit 6/23/2011 - results after further configuration

I went to Bouncy Castle page at http://www.bouncycastle.org/specifications.html#install
Scroll down to 5.0 Bouncy Castle Provider then read info under 5.1 Example. It makes mention of adding a parameter for the Bouncy Castle Provider to the java.security file. My file is under C:\Java\jdk1.6.0_22\jre\lib\security.

I added the following line to my file - security.provider.10=org.bouncycastle.jce.provider.BouncyCastleProvider

In addition, I discovered that I hadn't added the Bouncy Castle jars to the classpath, so I went ahead and did so.

Now after making these changes, recompiling and attempting to execute ClientSide.java I'm given the same exception : but maybe the focus should be on the part of the exception where it says this about bouncycastle provider -

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at org.bouncycastle.jce.provider.JDKPKCS12KeyStore.cryptData(Unknown Source) at org.bouncycastle.jce.provider.JDKPKCS12KeyStore.engineLoad(Unknown Source) 

@PeteyB - I'm certain that I installed the policy files correctly. Based on what I've stated here, is there anything else you can suggest I try? Can you look at the Bouncy Castle site @ http://www.bouncycastle.org/specifications.html#install and see if there is something I'm missing?

Answer 1

So the problem must be with your JCE Unlimited Strength installation.

Be sure you overwrite the local_policy.jar and US_export_policy.jar in both your JDK's jdk1.6.0_25\jre\lib\security\ and in your JRE's lib\security\ folder.

In my case I would place the new .jars in:

C:\Program Files\Java\jdk1.6.0_25\jre\lib\security

and

C:\Program Files\Java\jre6\lib\security

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If you are running Java 8 and you encounter this issue. Below steps should help!

Go to your JRE installation (e.g - jre1.8.0_181\lib\security\policy\unlimited) copy local_policy.jar and replace it with 'local_policy.jar' in your JDK installation directory (e.g - jdk1.8.0_141\jre\lib\security).