4 ms·

Are you arguing in favor of developer laziness? An average programmer should be able to understand the use cases for HMAC within a couple hours or so, given no

by sk5t 12y ago

Are you arguing in favor of developer laziness? An average programmer should be able to understand the use cases for HMAC within a couple hours or so, given nothing but the Wikipedia page and an IDE or REPL, and knowing about MACs might prevent him from cooking up all manner of broken security protocols in the future.

tinco 12y ago
The risk is that a developer might not realize there is a significant difference between just encrypting something, and using a MAC.
- deleted 12y ago
  [deleted]
michael_storm 12y ago
Well, I'm certainly not in favor of name-calling like that. HMACs don't provide any greater provable security guarantees than a database row in this scenario, so it comes down to implementation. HMACs are harder if you're not familiar with them, but almost everyone is familiar with a database. On the other hand, HMACs make the security of the overall system easier to verify, assuming HMACs are used correctly - but it's harder for newcomers to use them correctly. I'm saying that in this scenario, it doesn't make much of a difference which system is used. So the author shouldn't be quite so forceful in telling people to use a crypto primitive outside of their comfort zone for minimal benefit. I'd rather use a system written by someone confident in their DB solution, rather than someone who learned their HMAC solution in a couple of hours on Wikipedia.
skybrian 12y ago
How confident should the average developer be that they are able to create a secure crypto implementation in a couple of hours, based on some possibly-dubious advice they read in Wikipedia? I would argue that they shouldn't be very confident in this. The first thing you learn about crypto is that it's harder than it looks and best left to experts. Knowing when it's actually okay is difficult. At the very least, I'd expect that they ask for a review from someone who does know what they're doing, and how many developers who don't work at a big Internet company have a spare security expert handy?
- vidarh 12y ago
  Nobody is suggesting the developer should roll their own crypto. Pretty much every language out there have mature packages for HMAC's. What you need to know are a few basic things about how to use them to verify the integrity of a message.

by sk5t 12y ago

tinco 12y ago

The risk is that a developer might not realize there is a significant difference between just encrypting something, and using a MAC.

deleted 12y ago
[deleted]

michael_storm 12y ago

Well, I'm certainly not in favor of name-calling like that. HMACs don't provide any greater provable security guarantees than a database row in this scenario, so it comes down to implementation. HMACs are harder if you're not familiar with them, but almost everyone is familiar with a database. On the other hand, HMACs make the security of the overall system easier to verify, assuming HMACs are used correctly - but it's harder for newcomers to use them correctly. I'm saying that in this scenario, it doesn't make much of a difference which system is used. So the author shouldn't be quite so forceful in telling people to use a crypto primitive outside of their comfort zone for minimal benefit. I'd rather use a system written by someone confident in their DB solution, rather than someone who learned their HMAC solution in a couple of hours on Wikipedia.

skybrian 12y ago

How confident should the average developer be that they are able to create a secure crypto implementation in a couple of hours, based on some possibly-dubious advice they read in Wikipedia? I would argue that they shouldn't be very confident in this. The first thing you learn about crypto is that it's harder than it looks and best left to experts. Knowing when it's actually okay is difficult. At the very least, I'd expect that they ask for a review from someone who does know what they're doing, and how many developers who don't work at a big Internet company have a spare security expert handy?

vidarh 12y ago
Nobody is suggesting the developer should roll their own crypto. Pretty much every language out there have mature packages for HMAC's. What you need to know are a few basic things about how to use them to verify the integrity of a message.