BadPadding error trying to decrypt an encrypted text using RSA in java?

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Import java.awt. *; import javax.swing. *; import java.awt.event.

*; import java.net. *; import java.security. *; import javax.crypto.

*; import java.security.spec. RSAPublicKeySpec; import java.security.spec. RSAPrivateKeySpec; import java.math.

BigInteger; import java.io. *; public class te{ public static void main(String args)throws Exception, BadPaddingException{ String prm = "1356693815384374985786020038142368634468655364942303064968629976904326939996714307669149658585909884520869647876340752574207535591716198658155529888025635790189083217466451153081 269919397200690699534525643987865276277993880075999772490312417976020492378150309 39177321376213502000617956501365619136743391604527"; String pre = "19206980310240345089054650269266997266428253566713308882216247410797790472602897743665582297792448347068816600 544883817624645048626980493340327310227206380607181387937540249987606431866075725752492606382634185279280943886 308449677927309099658421773139598468152381904230858223190603151408714561182985778736217"; String pu = "13566938153843749857860200381423686344686553649423030649686299769043269399967143076691496585859098845208696478 763407525742075355917161986581555298880256357901890832174664511530812699193972006906995345256439878652762779938 8007599977249031241797602049237815030939177321376213502000617956501365619136743391604527"; String pue = "65537"; BigInteger m = new BigInteger(prm); BigInteger e = new BigInteger(pre); RSAPrivateKeySpec keySpec = new RSAPrivateKeySpec(m,e); KeyFactory fact = KeyFactory. GetInstance("RSA"); PrivateKey priKey = fact.

GeneratePrivate(keySpec); BigInteger m1 = new BigInteger(pu); BigInteger e1 = new BigInteger(pue); RSAPublicKeySpec keySpec2 = new RSAPublicKeySpec(m1, e1); KeyFactory fact2 = KeyFactory. GetInstance("RSA"); PublicKey pubKey = fact2. GeneratePublic(keySpec2); Cipher cipher = Cipher.

GetInstance("RSA/ECB/PKCS1Padding"); cipher. Init(Cipher. ENCRYPT_MODE, pubKey); String st = "Hello"; byte cleartext = st.getBytes(); byte ciphertext = null; ciphertext = cipher.

DoFinal(cleartext); Cipher cipher2 = Cipher. GetInstance("RSA/ECB/PKCS1Padding"); cipher2. Init(Cipher.

DECRYPT_MODE, priKey); byte cleartext2 = cipher2. DoFinal(cleartext); System.out. Println("the encrypted text is " + ciphertext.toString()); System.out.

Println("the decrypted text is " + cleartext2.toString()); } } ======================================== please help! I have spent hours trying to decrypt the string, but I keep getting the following error. Exception in thread "main" javax.crypto.

BadPaddingException: Data must start with zero at sun.security.rsa.RSAPadding. UnpadV15(Unknown Source) at sun.security.rsa.RSAPadding. Unpad(Unknown Source) at com.sun.crypto.provider.RSACipher.

A(DashoA13*..) at com.sun.crypto.provider.RSACipher. EngineDoFinal(DashoA13*..) at javax.crypto.Cipher. DoFinal(DashoA13*..) at te.

Main(te. Java:57) runtime-error link|improve this question asked Aug 18 '11 at 14:02Chris11.

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