On Mon, 2011-04-11 at 17:53 -0400, Dave Thompson wrote:
> >     From: owner-openssl-us...@openssl.org On Behalf Of pattabi raman
> >     Sent: Sunday, 10 April, 2011 08:14
> 
> >     I am using the below code snippet and am able to do the encytption. 
>        
> >     But I need to convert the encrypted format to Binary format inorder 
> > to pass the encrypted key to a different system. Any one pls suggest 
> > how to do the same ???
> 
> What do you mean encrypted key? There is no encrypted key.
> There is an encrypt*ion* key -- your file publkey.pem -- 
> which you should already have obtained *from* the recipient.
I'm not sure but probably what he means is converting PEM to DER.
I use openssl rsa command in times like this.
> 
> Do you mean the encrypted *data*, which is implied to be CardPin? 
> The output (data) from RSA_public_encrypt is ALREADY binary. 
> And it is NOT a null-terminated C string, so 
> 
> >     sprintf(encpin,
> 
> >     "%s",encrypted); 
> 
> etc is wrong about 99.999999% of the time.
> 
> Note that most actual systems do not use just encryption; 
> they usually need to combine with additional information. 
> Perhaps what you need is some ASN.1 structure *containing* 
> your data, or an XML structure, etc etc. 
> 
> Also, your code is hard to read. Frequently people post code 
> with too little white space, but yours has far too much.
> In several places you check for an error and print a message, 
> but then proceed to use the null pointer anyway; if/when the 
> error arises, this will be very wrong. In most cases there is 
> additional information that would be helpful in your error 
> message(s): errno/strerror for fopen (or other I/O) problems,
> or the OpenSSL error stack (e.g. ERR_print_errors_fp) for openssl.
> 
> Finally, you are assuming 256 bytes is enough for the RSA 
> encrypted value. If you ever get a publickey over 2048 bits 
> this will fail badly. It's safer to make this variable 
> if your environment or protocol allows that, or at least 
> check that the size of the key provided is not too big.
> 
> 
> 
> ______________________________________________________________________
> OpenSSL Project                                 http://www.openssl.org
> User Support Mailing List                    openssl-users@openssl.org
> Automated List Manager                           majord...@openssl.org


______________________________________________________________________
OpenSSL Project                                 http://www.openssl.org
User Support Mailing List                    openssl-users@openssl.org
Automated List Manager                           majord...@openssl.org

Reply via email to