siv2r

SignersContext Protocol Design Analysis

This document analyses how SignersContext flows through the BIP-445 FROST signing protocol, whether the implementation matches the stated design intent, what attacks a malicious coordinator can mount by equivocating on signers_ctx, how RFC 9591 compares, and what improved designs exist.

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1. What the Design Says

siv2r

#!/bin/bash
set -e

REPO_URL="https://github.com/siv2r/bip-frost-signing.git"
BRANCH="master"
TARGET="bip-0445"

git fetch "$REPO_URL" "$BRANCH"
REF="FETCH_HEAD"

siv2r

This is an adaptation of the MuSig2's partial signature forgery for the FROST protocol, described by Adam Gibson. You can find the original write-up here.

In FROST signing, a malicious participant could forge the partial signature (i.e., PartialSigVerify on it will succeed) of another participant without knowing their secret share, but only under the following conditions:

• The victim does not participate in the signing.
• The malicious participant impersonates the victim while also participating with their original share, making it appear as if two different participants are involved in the signing.

As a consequence, the malicious signing participant will be unable to create a valid partial signature for their original secret share.

Key Setup: Let's consider a 3-of-5 FROST policy among a group of participants ${P_1, P_2, P_3, P_4, P_5}$ with the following details:

siv2r

Strauss Algorithm Analysis

This document provides a detailed analysis of the Strauss multi-scalar multiplication algorithm as implemented in libsecp256k1's src/ecmult_impl.h.

1. Overview

The Strauss algorithm computes multi-point scalar multiplication:

R = n_1*P_1 + n_2*P_2 + ... + n_k*P_k + n_g*G

siv2r

#!/usr/bin/env python3

import subprocess
import os
import sys
import time
from openpyxl import Workbook
from openpyxl.styles import Font, Alignment

def run_command(cmd, log_file=None):

siv2r

#!/usr/bin/env python3

import subprocess
import os
import sys
import time
from openpyxl import Workbook
from openpyxl.styles import Font, Alignment

def run_command(cmd, log_file=None):

siv2r

This document provides specific instructions for your operation within this codebase. Please adhere to these guidelines strictly.

Planning Before Implementation (Important)

Before writing any code, you must create an implementation plan and get it approved.

• Create PLAN.md: Write your step-by-step plan to a PLAN.md file in the root directory. If there already exists a PLAN.md, overwrite it.
• Wait for Approval: Do not start implementing until the plan has been reviewed and approved.- Outline Different Approaches: If there are multiple, fundamentally different implementation strategies, present them in the plan. For each, list the pros and cons. Do not include minor variations.

Plan.md Template

## Context
<what we’re changing and why>

siv2r

Achieving warp speed with Rust

Contents:

• Number one optimization tip: don't
• Never optimize blindly
• Don't bother optimizing one-time costs
• Improve your algorithms
• CPU architecture primer
• Keep as much as possible in cache
• Keep as much as possible in registers

siv2r

Summer of Nix 2022: The Nix Book

tl;dr

Goals

• Improve the autodidactic Nix onboarding experience to increase community growth
• Provide a clear learning path from first impression down to source code

Tasks

siv2r

/* this is the main function of test.c of libsecp */
/* you can find my complete code here: https://github.com/siv2r/secp256k1/commit/b3a1437f715dad7478515a55728ecb12aaf4dad1 */

#include "modules/debug/main_impl.h"

int main() {
    unsigned char msg[40] = "Hey, this message is going to be hashed";
    unsigned char out[32];
    secp256k1_sha256 hash;