LLFourn

Unifing FROST and MuSig

There might be a secure scheme that non-interactively generates a n-of-n FROST key and from there you can interactively turn it into a t-of-n by issuing new shares (i.e. enrolment). I don't really know if this is a useful contribution even if it works. There might be some utility in not having multiple schemes but rather a one size fits all approach.

Idea

MuSig takes a "multiset" of n public keys and outputs a single aggregated key which takes n-of-n secret keys to sign. Set z_i = H(X_1,.. X_i, .. X_n, X_i) for i = 1,2, .. n.

LLFourn

OP_CTV and DLCs

Hi dlc-dev and bitcoin-dev,

tl;dr OP_CTV simplifies and improves performance of DLCs by a factor of a lot.

Introduction

Dryja introduced the idea of Discreet Log Contracts (DLC) in his breakthrough work[1]. Since then (DLC) has become an umbrella term for Bitcoin protocols that map oracle secret revelation to an on-chain transaction which apportions coins accordingly.

LLFourn

ª 0xAA
µ 0xB5
º 0xBA
À 0x41
Á 0x41
 0x41
à 0x41
Ä 0x41
Å 0x41
Æ 0xC6

LLFourn

sub MAIN(Int \m, Int \n, Int :$samples = 10_000) {
    my \q = 2 ** 19 - 1;
    my \m-n =  m ** n;

    # experiment should be done over a prime field so that it mirrors reality
    say "q = {q} (is-prime: {q.is-prime})";
    say "samples = {$samples}, m = {m}, n = {n}, m ^ n = {m-n}";

    sub count-collisions(@table) {
        # This line of code:

LLFourn

//! PoC style code for anticipating BIP-340 style signatures for PoC DLC stuff.
//!
//! WARNING this doesn't check that:
//!  1. Public keys have an even Y coordinate
//!  2. Public nonces have a square Y coordinate
//!
//! If the public keys are in the right form, then this should produce valid
//! BIP-340 signatures (to be fully compatible then the tag needs to be set
//! correctly).
//! Add to Cargo.toml:

LLFourn

This is a response I made to the thread that didn't make it into the archive (I think) :https://lists.linuxfoundation.org/pipermail/lightning-dev/2018-December/001752.html

---

Happy new year lightning-dev!

This topic is my main area of research at moment so I'm really happy to see a thread about it. In general I agree with ZmnSCPxj's analysis and conclusions. I'd like to add a couple of ideas to this discussion and would greatly appreciate some early peer review on them :)

HTLCs as American call options

LLFourn

class Rakudo {

    constant File $:install-to;
    constant $:checkout = '2017.07';
    constant File $:clone-to = './rakudo';
    constant GitHub $:zef-repo = 'ugexe/zef';
    constant GitHub $:repo = 'rakudo/rakudo';
    constant Bool $:debug-moar;

    static method install-deps on {

LLFourn

# So you want to pipe shell scripts to docker. But docker runs the container's command as PID 1. 
# Linux doesn't set up signal handlers for PID 1.
# This gives you the following problems:
# 1. The script can't kill itself:
echo 'kill $$; echo "Still alive"' | docker run -i --rm alpine sh 
# 2. You can't kill the script from outside with a normal kill:
echo "sleep 1000" | docker run -i --rm alpine sh & sleep 1 && kill $!
docker ps # it didn't die

#==== Solving problem 1 ====

LLFourn

BEFORE:
A 9.0422700
C 10.6984718
B 10.3635278
a 17.9581401
b 21.61539652
c 27.7105599
HEAD:
A 4.126187
C 4.918153

LLFourn

for i in $(seq 1 5); do
    ./install/bin/perl6 -e '"a" x 1000000000 ~ "b" ~~ /b/; say now - INIT now;'
done | awk '{ v += $0; i++; }; END { print v/i }'