Thanks Brian. Thanks everyone. This is great a big time saver for me. On Tue, Jul 3, 2018 at 4:00 PM, Brian Milby via use-livecode < use-livecode@lists.runrev.com> wrote:
> Initial code is posted here: > https://github.com/bwmilby/lc-community/tree/master/AES_Demo > > I'll update it later today with an updated version of the PHP that uses a > different IV for the return data. > > The good thing about how I've posted it is that PRs can be submitted and > integrated with edits to just the code (and I'll merge them into the stack > itself). If you do submit a PR, do not include the stack itself. Hold off > until v2 is posted though (I'm integrating an updated stack). > > After I post v2, I'm going to update the README with links to these threads > for reference. > > On Tue, Jul 3, 2018 at 2:27 PM, Tom Glod via use-livecode < > use-livecode@lists.runrev.com> wrote: > > > thank you for this .....I'm willing to post it too....was just thinking > if > > the goal is to nail down a best practice ..... then there may be a few > > suggestions from a few people and maybe a few revisits, so keeping up > with > > the mailing list or your personal site is not ideal for something that is > > being worked on in community. unfortunately i cannot add anything to the > > code except test it myself when the time comes. great job everyone this > > can be very helpful to a lot of livecode developers. > > > > > > > > On Tue, Jul 3, 2018 at 3:07 PM, Brian Milby via use-livecode < > > use-livecode@lists.runrev.com> wrote: > > > > > I think the IV vulnerability that I’m talking about is more theoretical > > > than an actual concern. From what I’ve read the attacker needs to be > able > > > to control/influence what is being encrypted for knowledge of the next > IV > > > to help (so they can use a known plain text to test their key > > hypothesis). > > > > > > And yes, the IV does make each encrypted message different even for the > > > same plain text. > > > > > > I didn’t fully work out the IV vulnerability but it did make sense how > it > > > would work. > > > > > > Thanks, > > > Brian > > > On Jul 3, 2018, 2:39 PM -0400, William Prothero <waproth...@gmail.com > >, > > > wrote: > > > > Brian, > > > > Thank you for your wisdom on this issue. I’m very interested in your > > > recommendations and they are inspiring me to do more Internet research. > > > > > > > > Just asking... > > > > You said that the attacker could figure out the next iv. Since I > append > > > the iv to the front of the encrypted data, the attacker will always > know > > > the iv, correct? As I understand, the iv is used to obfuscate the > > encrypted > > > data so it is more difficult for the attacker to decrypt the AES > > encrypted > > > data. A random iv is used so the attacker can’t get the key by entering > > > specific patterns of data and using the results. > > > > > > > > Darn, this is complicated! I can see why there are so many opinions. > I > > > read that some folks recommend that the iv be secret and others don’t. > > When > > > I look at the online discussions on stackoverflow, every comment is > > > responded to with a different suggestion, and I have no idea whether > the > > > commenter knows what he/she is talking about. There is also out of date > > > information to contend with. I also remember the horrible bug found in > > ssh > > > encryption. AES was developed and released November, 2001 and a lot of > > the > > > discussions are older. > > > > > > > > I think the basic thing we hope for is that the attacker doesn’t have > > > the key, and we need to do everything possible to keep it from > > determining > > > the key. The attacker can still decrypt with a brute force method that > > > tries all possible keys, but that’s probably rare in most cases, but > > > possible. > > > > > > > > I will modify the php to generate a new iv for the return data and > look > > > into the way I set the randomseed using the milliseconds. > > > > > > > > Thanks again, > > > > Bill > > > > > > > > William Prothero > > > > http://earthlearningsolutions.org > > > > > > > > > On Jul 3, 2018, at 9:31 AM, Brian Milby <br...@milby7.com> wrote: > > > > > > > > > > I just put the PHP on my server and it was able to handle the > > > randombytes IV without issue. > > > > > > > > > > The demo does not generate a new IV for the returned data which it > > > really should in production. > > > > > > > > > > From a security perspective, you assume that an attacker has access > > to > > > the code. From the encrypted message, an attacker could figure out your > > > next IV. > > > > > > > > > > _______________________________________________ > > > use-livecode mailing list > > > use-livecode@lists.runrev.com > > > Please visit this url to subscribe, unsubscribe and manage your > > > subscription preferences: > > > http://lists.runrev.com/mailman/listinfo/use-livecode > > > > > _______________________________________________ > > use-livecode mailing list > > use-livecode@lists.runrev.com > > Please visit this url to subscribe, unsubscribe and manage your > > subscription preferences: > > http://lists.runrev.com/mailman/listinfo/use-livecode > > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
