Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Implement constant-time division #9

Closed
mratsim opened this issue Feb 15, 2020 · 0 comments · Fixed by #185
Closed

Implement constant-time division #9

mratsim opened this issue Feb 15, 2020 · 0 comments · Fixed by #185
Labels
constant time ⏳ Enhancement is suitable for secret data

Comments

@mratsim
Copy link
Owner

mratsim commented Feb 15, 2020

Currently div2n1n (i.e. div 128 -> 64 and div 64 -> 32)
are implemented using assembly instructions.

Division in hardware is often implemented via microcode with timing that often depends on the operand values.

We need a guaranteed constant-time version of dividing 2 words by a word.
@mratsim mratsim added the constant time ⏳ Enhancement is suitable for secret data label Jun 6, 2020
mratsim added a commit that referenced this issue Feb 28, 2022
@mratsim
Implement fully constant-time division closes #2 closes #9
0298472
@mratsim mratsim linked a pull request Feb 28, 2022 that will close this issue
Constant time #185
Merged
3 tasks
mratsim added a commit that referenced this issue Feb 28, 2022
@mratsim
Constant time (#185)
26954f9 
* Implement fully constant-time division closes #2 closes #9

* constant-time hex parsing

* prevent cache timing attacks in toHex() conversion (which is only for test/debug purposes anyway)
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Assignees
No one assigned
Labels
constant time ⏳ Enhancement is suitable for secret data
Projects
None yet
Milestone
No milestone
Development

Successfully merging a pull request may close this issue.

Constant time mratsim/constantine
1 participant
@mratsim