horace.rb

horace.rb

require 'digest/sha1'

class Miner
  attr_reader :tree, :parent, :timestamp
  def initialize
    @tree=`git write-tree`.chomp
    @parent=`git rev-parse HEAD`.chomp
    @timestamp=12345
  end
 
def gitify_body_with_header(content)
"commit #{content.length}\0#{content}"
end
 
def prepare_index
  user_name = "user-udsg4qtp"
  `perl -i -pe 's/(#{user_name}: )(\d+)/$1 . ($2+1)/e' LEDGER.txt`
  `grep -q "#{user_name}" LEDGER.txt || echo "#{user_name}: 1" >> LEDGER.txt`
  `git add LEDGER.txt`
end

def git_sha(content)
  Digest::SHA1.hexdigest(gitify_body_with_header(content))
end
 
def difficulty
 "000001"
end
 
 def generate_body(counter)
    body="tree #{tree}
parent #{parent}
author CTF user <[email protected]> #{timestamp} +0000
committer CTF user <[email protected]> #{timestamp} +0000

Give me a Gitcoin

#{counter}
"
end
 
  def run
    threads = []
    10.times do |i|
      threads << Thread.new do
        start_time = Time.now
        counter = i * 1000000
        while true
          #puts "Thread #{i} trying with counter #{counter}"
          body = generate_body(counter)
          sha = git_sha(body)
          counter += 1
          if sha < difficulty
            puts "THREAD #{i} got a hit!"
            puts "total time: #{Time.now.to_f - start_time.to_f}"
            puts "sha: #{sha}"
            puts "counter: #{counter}"
            puts "difficulty: #{difficulty}"
            File.open("output.txt", "w") do |f|
              f.write(body)
            end
            # prepare_index
            # `git hash-object -t commit output.txt -w`
            # `git reset --hard #{sha}`
            # `git push origin master`
          end
          if counter > (i+1) * 10000000
            break
          end
        end
      end
    end
    threads.map(&:join)
    puts "done"
  end
end
 
Miner.new.run

1. prepare_index from shell
2. run above
3. as soon as above completes "git hash-object -t commit output.txt -w"
4. git reset --hard sha result from 3
5. git push origin master
6. ???
7. profit