Public key encryption algorithm for files

Is there a public key algorithm
good for encrypting files (large ones)
or should I stick to secret
keys for that?
Thanks.

There is no good way to encrypt larga data amounts using public key.
The way to do this is to generate a random key for a symetric algorithm (like DES), encrypt the file with tis file, cipher the symetric key with the asymetric key and append the result to the ciphered file.
Good luck

Similar Messages

Powershell to classify files ( confidential, highly confidential, Business use, and Public ) and encrypt it for confidential & highly confidential types.

Hello Experts !!
I am wondering if PowerShell can be used to classify files ( confidential, highly confidential, Business use, and Public ) and encrypt it for confidential & highly confidential types.
I found some material for Windows Server 2008 R2 and Windows 8.1 but that doesn't seem convincing. I need it for Xp and Windows 7.
Thanks !

You may want to consider using FCI (File Classification Infrastructure) in Server 2012 R2. You will need FSRM (File Server Resource Manager), AD RMS (Active Directory Management Services), AD CS (Active Directory Certificate Services, and DAS (Dynamic Access
Control). You will also need a 2012 level forest and domain, and KDC support for claims, compound authentication, and Kerberos armoring.
Microsoft has already developed the software foundation to do exactly what you're looking for at an enterprise scale. It may be easier to implement it, instead of reinventing the wheel..
Sam Boutros, Senior Consultant, Software Logic, KOP, PA http://superwidgets.wordpress.com (Please take a moment to Vote as Helpful and/or Mark as Answer, where applicable)

Public key encrypt/decrypt app

Hi all,
Does anyone know of a public key encrypt/decrypt ipad app (IOS5). I use gpgtools on the imac (lion 7.2) and put spreadsheets, docs, and the like into dropbox. I have the dropbox app on the ipad. It opens non-encrypted files just fine; however, if they are encrypted - no soap. I need something that works with dropbox, or provides a dropbox-like repository.
Searching the store gives me a couple of email encrypters but nothing for files.
Many thanks for any help,
Best,

By how much is the file size increasing? Depending on how you do the actual encryption, it can easily grow a bit due to varying headers and some padding, but it shouldn't be a significant part of the file size if the file is reasonably big.
If, however, the file size grows by some significant factor (say your output is 2 time the size of the input), then there is some problem that you should look into.

Renewing public key certificate used for Seeburger AS2

My general question is when a public key certificate, used for Seeburger AS2 payload decryption and digital signatures, needs to be renewed, how carefully do the certificate renewal steps need to be coordinated for a seamless transition? More specifically...
1. Once we import the CSR response from the CA, will the public key currently used by our partner become invalid, or will it continue to work until its expiration date?
2. Will our partner be able to validate our signature after the new CSR has been imported, but prior to them applying the new public key certificate in their system?
3. Or can we renew the certificate, import the CSR request, provide our partner with the renewed certificate, and let them apply the certificate at their own volition, provided they do it prior to the original certificate expiration?

Hi Kurt
In my experience, the renewal/replacement of AS2 certificates for encryption/decryption & signing/authentication requires coordinated effort on both sides.
This is because AS2 uses asymmetrical encryption, so both parties need to use the same pair of certificates at the same time, i.e. you encrypt on your private key, and partner decrypt on the public key matching your private key. If the keys used do not belong to the same pair, then decryption will not work.
I'm not sure what AS2 software your partner uses and if it has the feature of automatic rollover of certificate, but PI/Seeburger does not. The approach in PI/Seeburger can either be one of the following:-
i) import new cert replacing original cert of the same name
ii) import new cert into new name, manually update sender/receiver agreements
Due to the manual nature of the tasks, normally it requires coordinated effort during a cutover window.
Rgds
Eng Swee

Configuration of Public Key Authentication Policy for SFTP on OAG 11.1.2.2

Hi
I'm working on the configuration of an SFTP server over OAG, using both password and public key authentication.
This particular listener need 3 policies:
- Password Authentication
- Public Key Authentication
- File upload
Both File upload and password auth are working OK, but I've been having a hard time with the PK policy. This policy uses the attribute ${authentication.subject.public.key} to store the PK info, which I confirmed is being sent to the gateway (as modulus + public exponent), however I can not find a way to verify the key received with the ones on the Key Pairs store.
OAG Version is 11.1.2.2
Any comments?

Hi a82383ca-36ac-49d5-aa6e-c3307f7e56e1,
It would probably help if you place this question under the community for product you have questions about. I will see if I can help you move it to the proper one by asking around.
Best regards,
VictorI

Public Key Encryption

Hi guys,
I have to sign some data (a byte array) using a Public Key.
How can I do that?
(I know it's a bit strange..but I have to do this....)
Thanks a lot...bye!!

What you're really asking for is to do something with the data that only the owner of the Private Key can use. What you should be looking at is encryption with the Public Key and not Signing with the Public Key. You will find many examples on this forum, in the JCE web-pages at Sun and in David Hook's Book "Beginning Cryptography in Java".

How to obtain public key from a .crt file

Hi
I am new to cryptography Please correct me if my understanding regarding the digital signature is correct and i need help to get the public key.
I have a x.crt file which contains following fields
1) x
2)y
3) Certificate
this certificate contains following fields
certificate version
owner id
name
public key
signature (which is obtained by signing from start of x.crt till public key with private key)
now i need to verify whether the signature for that i need to get the public key & signature from this .crt file. Is it how i need to verify the certificate ?? please help me as I am a newbie in cryptography

Hi all
Thanks for the reply
So to get the public key now i used the following code
byte[] dataPub = new byte[256]; // size of the public key
try {
                    byteArrayInputStream.read(dataPub);
               } catch (IOException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
          BigInteger modulus = new BigInteger(dataPub);
     BigInteger exponent = new BigInteger("65537"); // specified in the document
     RSAPublicKeySpec rpks = new RSAPublicKeySpec(modulus, exponent);
     KeyFactory kf = null;
               try {
                    kf = KeyFactory.getInstance("RSA");
               } catch (NoSuchAlgorithmException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
     try {
                    pk = kf.generatePublic(rpks);
                    System.out.println("Pb Key----------------:"+pk.toString());
               } catch (InvalidKeySpecException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
When I convert the pk.toString I am getting a negative modulus value . Can the modulus value be negative ??
Edited by: 800317 on Oct 8, 2010 5:51 AM

Biztalk AS2 encryption error for file bigger than 100MB

I am getting following error when I am trying to receive file bigger than 100 MB. I was getting same error when I was trying file bigger than 5MB and I applied windows CU5. Now I can receive big file (I tested till 60 MB). New file which is coming is 110MB
and we start getting this error.
Can somebody help me to figure out this issue.
I am using Biztalk 2010 with windows 2008 server
A message received by adapter "HTTP" on receive location "RecLocAS2All" with URI "/xxxxxx/BTSHTTPReceive.dll" is suspended.
Error details: An output message of the component "Microsoft.BizTalk.EdiInt.PipelineComponents" in receive pipeline "Microsoft.BizTalk.EdiInt.DefaultPipelines.AS2Receive, Microsoft.BizTalk.Edi.EdiIntPipelines, Version=3.0.1.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35" is suspended due to the following error:
An error occurred when decrypting an AS2 message..
The sequence number of the suspended message is 2.

I tried passthrough pipeline and I can receive encrypted file.Now trying to write code to decrypt it but I can not. Based on certificate I can say it is RSASHAI, so using it for decrypt. But getting error at Convert.FromBase64String(text) where text
is encrypted test from file.
I am getting following error
The input is not a valid Base-64 string as it contains a non-base 64 character,
more than two padding characters, or an illegal character among the padding characters.
Can somebody help me to understand it and resolve this. Mean time trying
to convene customer for compressed file .Please help me to understand above error.

Algorithm for File IO

Hello All
Can any one inform me on how to find out if a binary file is a text file or a try binary. There is a class that reads all files as binary (both text and binary). I need to be able to distinguish at run-time whether the file is text (i.e. .txt, .rtf, .sql files are considered text) and binary
Thanks

You can have some heuristics, both on octet value distribution and also some unicode byte-order marks (see the XML spec for some algorithms for guessing different text encodings). For RTF and SQL you also have definite grammars they must obey. But you won't ever get a 100% accurate test.
Pete

Setting up CA for private/public key encryption on a Tiger server

If someone could help me get started or lead me somewhere that would be great.
Either for a mac or windows client, preferably both.
Thank you,
Tadashi

You'll find plenty of info at:
http://afp548.com
There's an article on setting up a CA and rolling your own cert.
Jeff

Key Field Value for File Adapter Sender Wildcard

Hello everybody, is there a way to use a wildcard for the property of NamA.keyFieldValue in the cc for a Fils Sender????, here's an example why, I need to take some Files via PI 7.0 and my key filed can change according to the file an example is that in a file can be HF28 and in another file can be HF29, the only character that is going to be constant is the H, I would really appreciate any suggestions, thanks in advance.
Regards,
Julio Cesar

Hi Julio
File sender adapter will read the file using FCC
Key Field Value entry is mandatory if the key field name is set. Otherwise, the entry can be ignored
http://help.sap.com/saphelp_nw70/helpdata/EN/34/393071e9b998438ddb8ce97cd617a1/frameset.htm
Content Conversion ( The Key Field Problem )
Thanks
Gaurav Bhargava

Key field values for file content conversion at sender communicationchannel

Hi all,
I am working on scenario File to Idoc.In this scenario at the sender side we configure the file content conversion for .CSV file.
In the flat file i am having more than one orders, XI will pick the file and creates a separate Idoc for each sales order at r/3.
We have similar fields "Order Item Number" both header and item.
If we got '00000' on the Header item then it should create a new idoc at the r/3 side other wise it will create line item.
Order item number will be 00000 for header but it will differ from order item to item.
source structure
Order Header
Order type
Sold-to-code
PO number
Order item number
Order date
AdresName1
AdresName2
Street and House number
Postal Code
City
Country Code
Filler
Order Item
Order type
Sold-to-code
PO number
Order item number
Order date
Product code
Order quantity
Item text
Filler
Now I have some questions....
I don't have standard filed values to give the key fileds at source structure.
I need to create the Idoc at r/3 system for each individual record.
Is it possible to create new idoc with out using the Key filed value?
If it is possible then how can i proceed with fcc?
please give me your valuable suggestions
Best Regards,
satya
Edited by: satyatanuku on Mar 3, 2010 1:41 PM
Edited by: satyatanuku on Mar 3, 2010 1:42 PM
Edited by: satyatanuku on Mar 3, 2010 1:44 PM

Hi,
Just check the Content Conversion Parameters- Recordset Structure.
If you have filled in this parameter with
Header,1,Item,1
then change it to
Header,1,Item,3
Regards
Chandra

How encrypt msg with Public Key ?

I want to encrypt my Session Key with the public key of the recipient but how can I do ?
I know how to encrypt with the Secret Key but not with the Public Key.
Thanks for response
Nicolas

It depends on the cryptosystem of which the public key you are having.
If it is of RSA then you have to get the cipher of RSA and pass the session key bytes as input to it.

How to get Public Key Remainder?

Hi Friends..
Sorry, i have a little doubt regarding the Public Key Remainder..
What is Public Key Remainder used for?.. is it a part of Public Key?.. How to get it from Public Key, especially in Java?
As far as i know that the Public Key is constructed with Modulus and Exponent, and with this we can Encrypt and Verify data was signed by Private Key..
In Java, we can expose Public Key's modulus and public exponent using RSAPublicKey, there's no method to expose Public Key's Remainder..
Please help me regarding this..
Thanks

Leonardo Carreira wrote:
Hi Shane,
Thanks for your reply.. :)
safarmer wrote:
In that case the exponent and remainder are you public key (exponent and modulus) and the certificate is defined in the definitions section of Book 3. It is a secure way of verifying the public key and it's owner through a trusted certification authority.
EMV Book 3 tends to use Remainder and Modulus interchangeably.You mean, the Issuer (in this case one of E,M, and V) should provide 2 certificates for 1 card?..
This is implemented on SDA or DDA?..
Sorry, i'm still have no idea..
The Remainder and Modulus should be used interchangeably?..
How the Host and Card can decides in each transaction whether it will use Remainder or Modulus?..I mean that the terminology is used interchangeably. They refer to the same thing as far as the actual key is concerned.
Cheers,
Shane

Solaris 9 LDAP client sun_ssh public key authentication

I have directory server 6.0 up on solaris 9 system and I have a couple of solaris 9 system migrated to LDAP client. I need to configure ssh public key authentication on two Solaris 9 LDAP clients. However, I seem can't make it working. I have done 1) generate rsa public/private key pairs on one host 2) cat public key to the authorized_keys file on another host. I checked the permission on $HOME and $HOME/.ssh, they both set to 700. The file permission are also correct. But I still get prompt when ssh from one LDAP client to another. If I add my password/shadow entry back to local files, then public key authentication works. My /etc/pam.conf is set up according to the Sun documentation for LDAP client. In /etc/nsswitch.conf
passwd: compat
passwd_compat: ldap
shadow: files ldap
group: files ldap
netgroup: ldap
loginShell does exist for the user.and LDAP entry has objectClasses 'posixAccount' and 'shadowAccount'
I have latest patch 112960 installed on all of LDAP clients.
What am I missing here?
Thanks,
--xinhuan

One more thing - I have latest patch 112960 installed on all of LDAP clients.
--xinhuan

Public key encryption algorithm for files

Similar Messages

Maybe you are looking for