Mixing
Length of the decryption(RSA) string is changing
I have a String which is encrypted with RSA algorithm, When i was trying to decrypt it's working fine.The decryption output will be in byte.
My question is when i trying to convert the byte to a new String(decrypted String) it's getting different length .
If i try with a random string the length is remains same.But if i decrypt the
generated aesKey(AES) the length of the byte is changing while conversion of new String(decrypted String).
Why i am getting different length incase of aesKey decryption???
Is there any difference between "random string" and "generated aeskey"
String ==
"t8xypyI6gKlKTkt4Qec7FCor4EpukZXqYQcIDm6YvbtRB9+YBrX0CqyoHOHN91T8RBQS/JD2osbf4ao9Y"SgNbzhfDa2NpJKMEIBWH4TNlF4Ngb8yWdSm3hz3l8FdeFUIy3pyCxkLjU8n4VAxsmgoIQbgd7DJuPiSMZBA9/IVlcCfo/tZjMtSkezITtoT5aVvLxLaTsp08UREdalvXxb5USKi3cAEdqR9TmLJxB004IMv5Eiuvdmcc3fJzO6mnwiHPuGKArd9LjjiqbPQ75uc8NDOFrvleLc5KwSuThS5Xx7tR1qfoX6qefh6SD7FRk5UzyCEnv+eD+mCQ588Jam1A==";
****The above string is encrypted form of the aesKey(generated by KeyGenerator)
If i decrypt this string by using RSA----
private String decrypt(String text, Key privatekey) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
byte dectyptedText = null;
Cipher cipher = Cipher.getInstance("RSA/ECB/OAEPPadding");
cipher.init(Cipher.DECRYPT_MODE, privatekey);
dectyptedText = cipher.doFinal(Base64.getDecoder().decode(text));
System.out.println(dectyptedText.length); //32
System.out.println(new String(dectyptedText).length()); //30
System.out.println(new String(dectyptedText).getBytes().length); //60
return new String(dectyptedText);
}
above, The length is changing in byte string conversions.
Suppose if i encrypt and decrypt with a normal string the lengths are not changing????why????
java algorithm security aes rsa
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
add a comment |
I have a String which is encrypted with RSA algorithm, When i was trying to decrypt it's working fine.The decryption output will be in byte.
My question is when i trying to convert the byte to a new String(decrypted String) it's getting different length .
If i try with a random string the length is remains same.But if i decrypt the
generated aesKey(AES) the length of the byte is changing while conversion of new String(decrypted String).
Why i am getting different length incase of aesKey decryption???
Is there any difference between "random string" and "generated aeskey"
String ==
"t8xypyI6gKlKTkt4Qec7FCor4EpukZXqYQcIDm6YvbtRB9+YBrX0CqyoHOHN91T8RBQS/JD2osbf4ao9Y"SgNbzhfDa2NpJKMEIBWH4TNlF4Ngb8yWdSm3hz3l8FdeFUIy3pyCxkLjU8n4VAxsmgoIQbgd7DJuPiSMZBA9/IVlcCfo/tZjMtSkezITtoT5aVvLxLaTsp08UREdalvXxb5USKi3cAEdqR9TmLJxB004IMv5Eiuvdmcc3fJzO6mnwiHPuGKArd9LjjiqbPQ75uc8NDOFrvleLc5KwSuThS5Xx7tR1qfoX6qefh6SD7FRk5UzyCEnv+eD+mCQ588Jam1A==";
****The above string is encrypted form of the aesKey(generated by KeyGenerator)
If i decrypt this string by using RSA----
private String decrypt(String text, Key privatekey) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
byte dectyptedText = null;
Cipher cipher = Cipher.getInstance("RSA/ECB/OAEPPadding");
cipher.init(Cipher.DECRYPT_MODE, privatekey);
dectyptedText = cipher.doFinal(Base64.getDecoder().decode(text));
System.out.println(dectyptedText.length); //32
System.out.println(new String(dectyptedText).length()); //30
System.out.println(new String(dectyptedText).getBytes().length); //60
return new String(dectyptedText);
}
above, The length is changing in byte string conversions.
Suppose if i encrypt and decrypt with a normal string the lengths are not changing????why????
java algorithm security aes rsa
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
share the code. I'm not sure what is your problem.
– piotr szybicki
Nov 20 '18 at 10:29
yes,I shared the code Please look into it once..
– Ram a Rao
Nov 20 '18 at 10:59
I cannot make sense of your question. First you're talking about a String, then you're talking about an AES key. It makes no sense to convert an AES key to a String using thenew String()constructor.
– James K Polk
Nov 20 '18 at 14:41
add a comment |
I have a String which is encrypted with RSA algorithm, When i was trying to decrypt it's working fine.The decryption output will be in byte.
My question is when i trying to convert the byte to a new String(decrypted String) it's getting different length .
If i try with a random string the length is remains same.But if i decrypt the
generated aesKey(AES) the length of the byte is changing while conversion of new String(decrypted String).
Why i am getting different length incase of aesKey decryption???
Is there any difference between "random string" and "generated aeskey"
String ==
"t8xypyI6gKlKTkt4Qec7FCor4EpukZXqYQcIDm6YvbtRB9+YBrX0CqyoHOHN91T8RBQS/JD2osbf4ao9Y"SgNbzhfDa2NpJKMEIBWH4TNlF4Ngb8yWdSm3hz3l8FdeFUIy3pyCxkLjU8n4VAxsmgoIQbgd7DJuPiSMZBA9/IVlcCfo/tZjMtSkezITtoT5aVvLxLaTsp08UREdalvXxb5USKi3cAEdqR9TmLJxB004IMv5Eiuvdmcc3fJzO6mnwiHPuGKArd9LjjiqbPQ75uc8NDOFrvleLc5KwSuThS5Xx7tR1qfoX6qefh6SD7FRk5UzyCEnv+eD+mCQ588Jam1A==";
****The above string is encrypted form of the aesKey(generated by KeyGenerator)
If i decrypt this string by using RSA----
private String decrypt(String text, Key privatekey) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
byte dectyptedText = null;
Cipher cipher = Cipher.getInstance("RSA/ECB/OAEPPadding");
cipher.init(Cipher.DECRYPT_MODE, privatekey);
dectyptedText = cipher.doFinal(Base64.getDecoder().decode(text));
System.out.println(dectyptedText.length); //32
System.out.println(new String(dectyptedText).length()); //30
System.out.println(new String(dectyptedText).getBytes().length); //60
return new String(dectyptedText);
}
above, The length is changing in byte string conversions.
Suppose if i encrypt and decrypt with a normal string the lengths are not changing????why????
java algorithm security aes rsa
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
I have a String which is encrypted with RSA algorithm, When i was trying to decrypt it's working fine.The decryption output will be in byte.
My question is when i trying to convert the byte to a new String(decrypted String) it's getting different length .
If i try with a random string the length is remains same.But if i decrypt the
generated aesKey(AES) the length of the byte is changing while conversion of new String(decrypted String).
Why i am getting different length incase of aesKey decryption???
Is there any difference between "random string" and "generated aeskey"
String ==
"t8xypyI6gKlKTkt4Qec7FCor4EpukZXqYQcIDm6YvbtRB9+YBrX0CqyoHOHN91T8RBQS/JD2osbf4ao9Y"SgNbzhfDa2NpJKMEIBWH4TNlF4Ngb8yWdSm3hz3l8FdeFUIy3pyCxkLjU8n4VAxsmgoIQbgd7DJuPiSMZBA9/IVlcCfo/tZjMtSkezITtoT5aVvLxLaTsp08UREdalvXxb5USKi3cAEdqR9TmLJxB004IMv5Eiuvdmcc3fJzO6mnwiHPuGKArd9LjjiqbPQ75uc8NDOFrvleLc5KwSuThS5Xx7tR1qfoX6qefh6SD7FRk5UzyCEnv+eD+mCQ588Jam1A==";
****The above string is encrypted form of the aesKey(generated by KeyGenerator)
If i decrypt this string by using RSA----
private String decrypt(String text, Key privatekey) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
byte dectyptedText = null;
Cipher cipher = Cipher.getInstance("RSA/ECB/OAEPPadding");
cipher.init(Cipher.DECRYPT_MODE, privatekey);
dectyptedText = cipher.doFinal(Base64.getDecoder().decode(text));
System.out.println(dectyptedText.length); //32
System.out.println(new String(dectyptedText).length()); //30
System.out.println(new String(dectyptedText).getBytes().length); //60
return new String(dectyptedText);
}
above, The length is changing in byte string conversions.
Suppose if i encrypt and decrypt with a normal string the lengths are not changing????why????
java algorithm security aes rsa
java algorithm security aes rsa
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
edited Nov 20 '18 at 10:48
Ram a Rao
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
asked Nov 20 '18 at 10:25
Ram a RaoRam a Rao
34
34
share the code. I'm not sure what is your problem.
– piotr szybicki
Nov 20 '18 at 10:29
yes,I shared the code Please look into it once..
– Ram a Rao
Nov 20 '18 at 10:59
I cannot make sense of your question. First you're talking about a String, then you're talking about an AES key. It makes no sense to convert an AES key to a String using thenew String()constructor.
– James K Polk
Nov 20 '18 at 14:41
add a comment |
share the code. I'm not sure what is your problem.
– piotr szybicki
Nov 20 '18 at 10:29
yes,I shared the code Please look into it once..
– Ram a Rao
Nov 20 '18 at 10:59
I cannot make sense of your question. First you're talking about a String, then you're talking about an AES key. It makes no sense to convert an AES key to a String using thenew String()constructor.
– James K Polk
Nov 20 '18 at 14:41
share the code. I'm not sure what is your problem.
– piotr szybicki
Nov 20 '18 at 10:29
share the code. I'm not sure what is your problem.
– piotr szybicki
Nov 20 '18 at 10:29
yes,I shared the code Please look into it once..
– Ram a Rao
Nov 20 '18 at 10:59
yes,I shared the code Please look into it once..
– Ram a Rao
Nov 20 '18 at 10:59
I cannot make sense of your question. First you're talking about a String, then you're talking about an AES key. It makes no sense to convert an AES key to a String using the
new String() constructor.– James K Polk
Nov 20 '18 at 14:41
I cannot make sense of your question. First you're talking about a String, then you're talking about an AES key. It makes no sense to convert an AES key to a String using the
new String() constructor.– James K Polk
Nov 20 '18 at 14:41
add a comment |
1 Answer
1
active
oldest
votes
Likely, the decryptedText contains funny bytes. The documentation says:
public String(byte bytes)
Constructs a new
Stringby decoding the specified array of bytes using the platform's default charset. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.
The behavior of this constructor when the given bytes are not valid in the default charset is unspecified. The CharsetDecoder class should be used when more control over the decoding process is required.
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
add a comment |
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1 Answer
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1 Answer
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active
oldest
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oldest
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oldest
votes
Likely, the decryptedText contains funny bytes. The documentation says:
public String(byte bytes)
Constructs a new
Stringby decoding the specified array of bytes using the platform's default charset. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.
The behavior of this constructor when the given bytes are not valid in the default charset is unspecified. The CharsetDecoder class should be used when more control over the decoding process is required.
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
add a comment |
Likely, the decryptedText contains funny bytes. The documentation says:
public String(byte bytes)
Constructs a new
Stringby decoding the specified array of bytes using the platform's default charset. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.
The behavior of this constructor when the given bytes are not valid in the default charset is unspecified. The CharsetDecoder class should be used when more control over the decoding process is required.
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
add a comment |
Likely, the decryptedText contains funny bytes. The documentation says:
public String(byte bytes)
Constructs a new
Stringby decoding the specified array of bytes using the platform's default charset. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.
The behavior of this constructor when the given bytes are not valid in the default charset is unspecified. The CharsetDecoder class should be used when more control over the decoding process is required.
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
Likely, the decryptedText contains funny bytes. The documentation says:
public String(byte bytes)
Constructs a new
Stringby decoding the specified array of bytes using the platform's default charset. The length of the new String is a function of the charset, and hence may not be equal to the length of the byte array.
The behavior of this constructor when the given bytes are not valid in the default charset is unspecified. The CharsetDecoder class should be used when more control over the decoding process is required.
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
answered Nov 20 '18 at 20:02
user58697user58697
4,3431717
4,3431717
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
add a comment |
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
I'd bet OP's charset is UTF-8. AESkey is effectively random bytes, and statistically nearly half of them are invalid UTF-8; although not spec'ed in reality decoding substitutes U+FFFD which then re-encodes to 3 bytes, so you get a random length near 16+(3x16)=64 bytes. With the actual AES key value destroyed, of course. So don't do that.
– dave_thompson_085
Nov 21 '18 at 1:18
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
Right, If we convert the String to byte---> byte to String behavior is not changing, if we convert the byte to new String , The length of the byte is changing, it's might effect on the byte.
– Ram a Rao
Nov 23 '18 at 4:34
add a comment |
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share the code. I'm not sure what is your problem.
– piotr szybicki
Nov 20 '18 at 10:29
yes,I shared the code Please look into it once..
– Ram a Rao
Nov 20 '18 at 10:59
I cannot make sense of your question. First you're talking about a String, then you're talking about an AES key. It makes no sense to convert an AES key to a String using the
new String()constructor.– James K Polk
Nov 20 '18 at 14:41