bip-0374: fix challenge generation, use correct generator point #1734

1. 
   guggero commented at 3:01 pm on December 28, 2024: contributor

   Both generating and verifying a proof allows for specifying a custom generator point G. But that custom generator point was not passed into the dleq_challenge function, resulting in the default (secp256k1) generator point to be used. This lead to the test vectors being incorrect.

   Noticed this while re-implementing DLEQ proof generation and verification in Golang.

2. bip-0374: fix challenge generation, use correct G

   Both generating and verifying a proof allows for specifying a custom
   generator point G. But that custom generator point was not passed into
   the dleq_challenge function, resulting in the default (secp256k1)
   generator point to be used. This lead to the test vectors being
   incorrect.

   8bc42a2673
3. jonatack added the label Bug fix on Dec 28, 2024
4. 
   jonatack commented at 5:30 pm on December 28, 2024: member

   cc @andrewtoth @RubenSomsen @theStack for feedback
5. 
   jonatack commented at 5:33 pm on December 28, 2024: member

   utACK, at first glance the fix LGTM.
6. andrewtoth approved
7. 
   andrewtoth commented at 6:09 pm on December 28, 2024: contributor

   Thanks! Might make sense to also remove the default value for G in dleq_challenge.
8. bip-0374: remove default value for G in dleq_challenge

   To avoid the mistake fixed in the previous commit, we remove the default
   value from the G parameter of dleq_challenge.

   e141b9501d
9. 
   guggero commented at 8:43 pm on December 28, 2024: contributor

   Thanks! Might make sense to also remove the default value for G in dleq_challenge.

   Makes sense. Added a commit to remove the default value.

10. andrewtoth approved
11. 
    andrewtoth commented at 8:46 pm on December 28, 2024: contributor

    utACK e141b9501d6f0602c603ad044dfde06c9cb3613e
12. 
    jonatack commented at 9:17 pm on December 28, 2024: member

    ACK
13. jonatack merged this on Dec 28, 2024
14. jonatack closed this on Dec 28, 2024

    ---

15. 
    jonatack commented at 9:21 pm on December 28, 2024: member

    There are a couple of unrelated other issues with this file, if it is intended to be run:

    • File permissions, i.e. 755
    • File header #!/usr/bin/env python3
16. guggero deleted the branch on Dec 28, 2024
17. 
    theStack commented at 4:13 pm on December 30, 2024: contributor

    Post-merge ACK e141b9501d6f0602c603ad044dfde06c9cb3613e

    Thanks for fixing!

Contributors
guggero jonatack andrewtoth theStack

Labels
Bug fix