asymmetric encryption

[jessepinkman]

Hello,
In the OPCUA specification we should use an Asymmetric encryption (in my case RSA 256 oaep) to encrypt the "OpenSecureChannel request" and "OpenSecureChannel response".
My OpenSecureChannel request/response size = 2000 octets
RSA Algorithm support bloc size of ~217 octets or something like that (RSA blocSize = RSA_Size(key) - paddingSize)

How should i do to encrypt my request and my response
Should i use an operation mode (CBC for example) to split my plainText into a small blocs ?? Am i respecting the specification by doing that


Thank you

[Support Team]

Hello,

yes you are right the topic is not so easy, however it is solved when you use our commercial SDK because we have implemented the latest security functions in our UA Stacks, which we deliver together with the SDK. Furthermore we do test our implementation with all other commercial SDK providers and cross language (.NET, Java, ANSI C). Unfortunately we do not present our implemented solution to competitive developments, hoping you understand.

Having said that, you have two options:
1) ask the OPC Foundation
2) use our commercial SDK

Please send your purchase order to sales@unifiedautomation.com

Best Regards
Support Team

[jessepinkman]

Hello,
Thank you very much, I will do it.

Best regard,