Hi Cyptmon, > 1. Compute hash over this data using SHA-512. This gives me a 512 bit > hash. > 2. Now I have the public key for the key pair that was used to > generated the signature. I do a signature verification using RSA-1024 ... > where should I get started ...
If using RSA with Appendix, see http://www.codeproject.com/useritems/RsaSignatureAppendix.asp. Instead of RSASS<PKCS1v15, SHA>, use RSASS<PKCS1v15, SHA512>. If you are using RSA with Recovery, see the validat*.cpp included with Crypto++. PSSR is what you are intersted in. Since 32KB is large for a Recovery scheme, I would presume this is Appendix. > = 32KB/81MB seconds + one RSA verification (0.07 ms) [The number given > is for one operation and I believe thats for 1Kb as you mentioned in > your earlier reply, so I can use this directly for 512 bits?) You would probaby get the best results if you implemented the code and developed you're own benchmarks. You would probably have your numbers in less time it took to develop this email thread. > and how much time will it take to do the simple > thing i just described It is fairly trivial in Crypto++. It should take next to no time since Wei has provided the code in the validate and benchmark routines. Jeff On 10/6/07, Cyptmon <[EMAIL PROTECTED]> wrote: > > HI Tim > > Thanks for the reply > > I think I wasnt clear enough, so here is what I am going to do. I have > 32 KB of data which already has a signed hash (say Hash was generated > using SHA-512). Now what I want to do is verify this signature. So > this is what I will be doing > > 1. Compute hash over this data using SHA-512. This gives me a 512 bit > hash. > 2. Now I have the public key for the key pair that was used to > generated the signature. I do a signature verification using RSA-1024 > > So the total time I will calculate as : Time for Hashing 32KB + Time > for verifying it using the public key and hash > > = 32KB/81MB seconds + one RSA verification (0.07 ms) [The number given > is for one operation and I believe thats for 1Kb as you mentioned in > your earlier reply, so I can use this directly for 512 bits?) > > I think your earlier posts have made it clear, but I just want to be > sure if I am doing the right thing. > > Thanks for all the help > > One last thing, I would want to use crypto++ library to do the same, > where should I get started and how much time will it take to do the > simple thing i just described > > Thanks once again > > [ SNIP ] --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the "Crypto++ Users" Google Group. To unsubscribe, send an email to [EMAIL PROTECTED] More information about Crypto++ and this group is available at http://www.cryptopp.com. -~----------~----~----~----~------~----~------~--~---
