Interactive tool to check passwords against the HIBP API

pwned.rb

require 'digest/sha1'
require 'net/http'

API_ROOT = "https://api.pwnedpasswords.com/range/"

def split_sha(password)
  sha = Digest::SHA1.hexdigest(password).upcase
  [sha[0...5], sha[5..]]
end

def check_api(prefix)
  uri = URI("#{API_ROOT}/#{prefix}")
  resp = Net::HTTP.get_response(uri)
  if resp.code.to_i != 200
    puts "API failed, code: #{resp.code}"
    exit 1
  end

  return resp.body.lines.map { |line| line.chomp.split(":") }.to_h
end

def check(password)
  prefix, remainder = split_sha(password)

  check_api(prefix)[remainder]
end

# main

loop do
  print "Enter a password to check: "
  password = gets.chomp

  if count = check(password)
    puts "Password found. Count: #{count}"
  else
    puts "Password not found"
  end

  puts
end