Thanks Mark, New problem. Trying to use aes-256-ctr instead. I'm following the syntax in the dictionary but it throws a red cross on it:
encrypt tData using "aes-256-ctr" with key tMyKey and salt tMySalt What is wrong with this syntax that the auto language detector shows it as a mistake? Sean On Thu, 16 Dec 2021 at 16:45, Mark Waddingham via use-livecode < [email protected]> wrote: > On 2021-12-16 16:23, Sean Cole via use-livecode wrote: > > Hi all, > > I'm trying to use RSA to encrypt data from a text field like an address > > or > > notes. When I try to use the encrypt command I get a result 'message > > too > > long'. What is the method for encrypting long or large data? > > > > My current line of code: > > encrypt tData using rsa with public key tMyKey and > > passphrase tMyPass > > RSA encryption can only encrypt data up to a certain length (I can't > remember off the top of my head the exact relation, but it is related to > the size of the key) so it isn't designed to be used on arbitrary length > messages. > > Encrypting arbitrary length messages is the domain of symmetric > encryption functions - like AES and friends. > > The solution, therefore, is to combine the two: > > 1) Generate a random (using randomBytes()) fixed length encryption key > FixedKey > > 2) Encrypt the actual data using a symmetric algorithm with FixedKey > as password > > 2) Use RSA to encrypt the (fixed length!) key FixedKey > > 4) Make you message the RSA-encrypted FixedKey followed by the > encrypted data > > The RSA encrypted FixedKey will be a constant length, and thus you can > just split that off of the combined data, decrypt it using RSA and then > use the result to decrypt the payload. > > Hope this helps! > > Mark. > > -- > Mark Waddingham ~ [email protected] ~ http://www.livecode.com/ > LiveCode: Everyone can create apps > > _______________________________________________ > use-livecode mailing list > [email protected] > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > _______________________________________________ use-livecode mailing list [email protected] Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
