"lavu" <th******@yahoo.comwrote in message
news:11*********************@j44g2000cwa.googlegro ups.com...
>I am trying to provide some security to text files, by adding a
signature
at the end of each text file.
this signature needs to be generated by some kind of
hashing algorithm. so while sending the file,
i will sign the text file and at the receiving end,
the text file will be checked to make sure
that the hash code matches.
( not that it matters for this but my environment is c++ in vs.net2003)
any ideas about what kind of hash algorithm i could use ?
thanks in advance.
Hashes and digital signatures are not the same. Loosely, a signature on a
message is string which is the value of the hash of a message encrypted with
the signer's private key.
So the first thing you need to do is to decide whether you want a signature
or a hash. Just by the way, signatures usually imply the presence of a whole
infrastructure with a trusted "certificate authority".
Popular hash algorithms go by the name of SHA-1 (secure hash #1) and MD5
(message digest #5). Google is your friend.
Cryptography is a huge and hard-to-grok topic. You might want to start
reading here:
http://msdn2.microsoft.com/en-us/library/aa382450.aspx
or here
http://www.eskimo.com/~weidai/cryptlib.html
Regards,
Will