Objectmix
Tags Register Mark Forums Read

Java encryption <--> .NET encryption : Java

This is a discussion on Java encryption <--> .NET encryption within the Java forums in Programming Languages category; Hajo, I need to exchange encypted data between ..NET and Java environments. The first problem I encountered is that symmetric ciphers in .NET needs initialization vector and Java counterparts don't. Can some one point me out the place where I can find any practise and patterns for encrypted communication between Java and .NET ? thanks for any info Gawel...


Object Mix > Programming Languages > Java > Java encryption <--> .NET encryption

Reply

 

LinkBack Thread Tools
  #1  
Old 03-16-2005, 06:59 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Java encryption <--> .NET encryption

Hajo,
I need to exchange encypted data between
..NET and Java environments. The first
problem I encountered is that symmetric
ciphers in .NET needs initialization
vector and Java counterparts don't.

Can some one point me out the place
where I can find any practise and
patterns for encrypted communication
between Java and .NET ?

thanks for any info

Gawel
  #2  
Old 03-16-2005, 08:15 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

A bit of discussion and some sample code for this for 3DES case:
http://www.jensign.com/JavaScience/dotnet/NetDESEncrypt
- Mitch Gallant

"gawel" <gawelek@gazetamoveitout.pl> wrote in message news:d1978h$mo0$1@nemesis.news.tpi.pl...
> Hajo,
> I need to exchange encypted data between
> .NET and Java environments. The first
> problem I encountered is that symmetric
> ciphers in .NET needs initialization
> vector and Java counterparts don't.
>
> Can some one point me out the place
> where I can find any practise and
> patterns for encrypted communication
> between Java and .NET ?
>
> thanks for any info
>
> Gawel



  #3  
Old 03-16-2005, 10:15 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

Michel Gallant wrote:

> A bit of discussion and some sample code for this for 3DES case:
> http://www.jensign.com/JavaScience/dotnet/NetDESEncrypt


At first glance looks great. Thanks for it.
Did you do similar comparison with RSA ?


Gawel
  #4  
Old 03-16-2005, 10:49 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

One more thing.
In this article you mentioned that RSA
is not in JCE. But here I see RSA:
http://java.sun.com/j2se/1.4.2/docs/...uide.html#AppA


Can you explain me whre is the truth


Gawel
  #5  
Old 03-16-2005, 02:38 PM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

Pre JSE 1.5 RSA was only available for digital signature (not for encryption/enveloping).
However, provider was updated in JSE 1.5 to include RSA encryption capability:
http://java.sun.com/j2se/1.5.0/docs/...cements15.html

- Mitch Gallant

"gawel" <gawelek@gazetamoveitout.pl> wrote in message news:d19kov$82t$1@nemesis.news.tpi.pl...
> One more thing.
> In this article you mentioned that RSA
> is not in JCE. But here I see RSA:
> http://java.sun.com/j2se/1.4.2/docs/...uide.html#AppA
>
>
> Can you explain me whre is the truth
>
>
> Gawel



  #6  
Old 03-16-2005, 02:39 PM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

http://www.jensign.com/JavaScience/dotnet/RSAEncrypt
- Mitch

"gawel" <gawelek@gazetamoveitout.pl> wrote in message news:d19ipe$nun$1@nemesis.news.tpi.pl...
> Michel Gallant wrote:
>
> > A bit of discussion and some sample code for this for 3DES case:
> > http://www.jensign.com/JavaScience/dotnet/NetDESEncrypt

>
> At first glance looks great. Thanks for it.
> Did you do similar comparison with RSA ?
>
>
> Gawel



  #7  
Old 03-17-2005, 09:40 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

Michel Gallant wrote:
> A bit of discussion and some sample code for this for 3DES case:
> http://www.jensign.com/JavaScience/dotnet/NetDESEncrypt


I implemented AES using your pattern and all works great
except 256 bit keys. In this case I got exception about
not supported key length and in documentation is written
that JCE implementation of AES suppoerts 128, 192 and
256 bit keys.

One more thing, you can add to your article that
decrypted .NET bytes needs to be converted into String in Java
using following statement:

string plainDotNetText = new String(decryptedBytes, "UTF-16LE");


thanks once again for help


Gawel
  #8  
Old 03-18-2005, 09:02 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

Michel Gallant wrote:
> http://www.jensign.com/JavaScience/dotnet/RSAEncrypt


Hajo,

have you ever exchange RSA public key using Base64 between
Java and .NET? I have no problem with exchanging of
symmertic key(AES, DES) but for RSA I got modulus can
not be negative exception. I think it is connected with bytes
order but I do not know what is going on.



regards


Gawel
  #9  
Old 03-18-2005, 09:28 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

gawel wrote:

> Michel Gallant wrote:
>
>> http://www.jensign.com/JavaScience/dotnet/RSAEncrypt

>
>
> Hajo,
>
> have you ever exchange RSA public key using Base64 between
> Java and .NET? I have no problem with exchanging of
> symmertic key(AES, DES) but for RSA I got modulus can
> not be negative exception. I think it is connected with bytes
> order but I do not know what is going on.


I found the reason of problem.
I have 1024 bit RSA. Modulus in java
has 129 bits and privateExponnet has 129 bits
but in .NET modulus has 128 bits and private exponent
has 128 bits. Java adds leading 0 to modulus and privateExponent.
When you add this 0 all is ok. Can you explain it ?


regards

Gawel
  #10  
Old 03-18-2005, 10:43 AM
Junior Member
 
Join Date: Nov 2009
Posts: 0
Application Development is on a distinguished road
Default Re: Java encryption <--> .NET encryption

Shouldn't be a problem .. after all Modulus is simply a number and
same with exponent. That extra 0 is a leading 0 in Big Endian number
so has no significance. If you are careless with interpreting your bits
in swapping from little to big Endian .. it could cause a problem.
I think that "artifact" is documented in some of my C# source code :-)
- Mitch

"gawel" <gawelek@gazetamoveitout.pl> wrote in message news:d1eooe$e6s$1@nemesis.news.tpi.pl...
> gawel wrote:
>
> > Michel Gallant wrote:
> >
> >> http://www.jensign.com/JavaScience/dotnet/RSAEncrypt

> >
> >
> > Hajo,
> >
> > have you ever exchange RSA public key using Base64 between
> > Java and .NET? I have no problem with exchanging of
> > symmertic key(AES, DES) but for RSA I got modulus can
> > not be negative exception. I think it is connected with bytes
> > order but I do not know what is going on.

>
> I found the reason of problem.
> I have 1024 bit RSA. Modulus in java
> has 129 bits and privateExponnet has 129 bits
> but in .NET modulus has 128 bits and private exponent
> has 128 bits. Java adds leading 0 to modulus and privateExponent.
> When you add this 0 all is ok. Can you explain it ?
>
>
> regards
>
> Gawel



Reply

Thread Tools


Similar Threads

Thread Thread Starter Forum Replies Last Post
Encryption via C# Code vs. SQL Native Encryption usenet CSharp 0 11-28-2007 05:09 PM
Rijndael encryption - can I supply my own encryption key? usenet DOTNET 1 08-21-2007 05:49 PM
Java Stream Encryption usenet Java 9 01-04-2007 03:41 AM
GPG and java encryption/decryption usenet Java 0 09-12-2005 03:37 AM
RSA encryption with private key in Java usenet Java 1 05-13-2005 04:28 PM


All times are GMT -5. The time now is 12:42 PM.

Managed by Infnx Pvt Ltd.