Date: Thu, 20 May 1999 10:40:38 -0400
From: "Aaron M. Stromas" <ams@us.oracle.com>
To: java-security@java.sun.com
Subject: padding problem
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Content-Type: text/plain; charset="us-ascii"
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hi,
i initialise my Cipher object as shown below for both encryption and
decryption. my problem is that i keep getting the BadPaddingException.
>From what i was able to gather, specifying PKCS5Padding should've taken
care of the padding problem. obviously, i misunderstood something.
please, advise what i am doing wrong and what i should be doing to
correct my error. tia,
here is what i do to encrypt:
try {
PBEParameterSpec paramSpec = new PBEParameterSpec(salt,
iterations);
PBEKeySpec keySpec = new
PBEKeySpec(args[0].toCharArray());
SecretKeyFactory kf =
SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = kf.generateSecret(keySpec);
Cipher cipher =
Cipher.getInstance("PBEWithMD5AndDES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
byte[] encrypted = cipher.doFinal(args[1].getBytes());
String encoded = new String(Base64.encode(encrypted));
.....
and this is how i attempt to decrypt
.....
PBEParameterSpec paramSpec = new PBEParameterSpec(salt,
iterations);
PBEKeySpec keySpec = new PBEKeySpec(passwd.toCharArray());
SecretKeyFactory kf =
SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = kf.generateSecret(keySpec);
cipher =
Cipher.getInstance("PBEWithMD5AndDES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, paramSpec);
byte[] cleartext =
cipher.doFinal(Base64.decode(cryptotext.getBytes()));
the last line results in exception:
javax.crypto.BadPaddingException: Given final block not properly
padded
at com.sun.crypto.provider.DESCipher.engineDoFinal(Compiled
Code)
at com.sun.crypto.provider.DESCipher.engineDoFinal(Compiled
Code)
at
com.sun.crypto.provider.PBEWithMD5AndDESCipher.engineDoFinal(Compiled
Code)
at javax.crypto.Cipher.doFinal(Compiled Code)
at Ldap.decrypt(Compiled Code)
at Ldap.search(Compiled Code)
at Main.main(Compiled Code)
i tested base64 encoding/decoding and eliminated it as a cuprit. again,
thanks for your help.
-- Aaron Stromas | "Tick-tick-tick!!!... ja, Pantani is weg..." Oracle Corp | BRTN commentator +1 703.708.49.33 | L'Alpe d'Huez 1995 Tour de France
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<!doctype html public "-//w3c//dtd html 4.0 transitional//en"> hi,
i initialise my Cipher object as shown below for both encryption and decryption. my problem is that i keep getting the BadPaddingException. >From what i was able to gather, specifying PKCS5Padding should've taken care of the padding problem. obviously, i misunderstood something. please, advise what i am doing wrong and what i should be doing to correct my error. tia,
here is what i do to encrypt:
try {
PBEParameterSpec paramSpec = new PBEParameterSpec(salt, iterations);
PBEKeySpec keySpec = new PBEKeySpec(args[0].toCharArray());
SecretKeyFactory kf = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = kf.generateSecret(keySpec);
Cipher cipher = Cipher.getInstance("PBEWithMD5AndDES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);
byte[] encrypted = cipher.doFinal(args[1].getBytes());
String encoded = new String(Base64.encode(encrypted));
.....and this is how i attempt to decrypt
.....
PBEParameterSpec paramSpec = new PBEParameterSpec(salt, iterations);
PBEKeySpec keySpec = new PBEKeySpec(passwd.toCharArray());
SecretKeyFactory kf = SecretKeyFactory.getInstance("PBEWithMD5AndDES");
SecretKey key = kf.generateSecret(keySpec);
cipher = Cipher.getInstance("PBEWithMD5AndDES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, key, paramSpec);byte[] cleartext = cipher.doFinal(Base64.decode(cryptotext.getBytes()));
the last line results in exception:
javax.crypto.BadPaddingException: Given final block not properly padded
at com.sun.crypto.provider.DESCipher.engineDoFinal(Compiled Code)
at com.sun.crypto.provider.DESCipher.engineDoFinal(Compiled Code)
at com.sun.crypto.provider.PBEWithMD5AndDESCipher.engineDoFinal(Compiled Code)
at javax.crypto.Cipher.doFinal(Compiled Code)
at Ldap.decrypt(Compiled Code)
at Ldap.search(Compiled Code)
at Main.main(Compiled Code)i tested base64 encoding/decoding and eliminated it as a cuprit. again, thanks for your help.
-- Aaron Stromas | "Tick-tick-tick!!!... ja, Pantani is weg..." Oracle Corp | BRTN commentator +1 703.708.49.33 | L'Alpe d'Huez 1995 Tour de France--------------BE4A5E3958674A01019E6EB5--