Ruby 错误：在“进程中的块”中：“4”的未定义方法“^”：字符串（NoMethodError）

Question

尝试运行 rc4 算法但无法识别 XOR 方法？还是发生了其他事情？当它到达 def process(text) 时出现错误。

错误：

rc4.rb:26:in block in process': undefined method^' for "4":String (NoMethodError) 来自 rc4.rb:26:in upto' from rc4.rb:26:inprocess' 来自 rc4.rb:21:in encrypt' from rc4.rb:48:in'

代码：

class Rc4

def initialize(str)
    @q1, @q2 = 0, 0
    @key = []
    str.each_byte {|elem| @key << elem} while @key.size < 256
    @key.slice!(256..@key.size-1) if @key.size >= 256
    @s = (0..255).to_a
    j = 0 
    0.upto(255) do |i| 
      j = (j + @s[i] + @key[i] )%256
      @s[i], @s[j] = @s[j], @s[i]
    end    
  end

  def encrypt!(text)
    process text
  end  

  def encrypt(text)
    process text.dup
  end 

  private

  def process(text)
    0.upto(text.length-1) {|i| text[i] = text[i] ^ round}
    text
  end

  def round
    @q1 = (@q1 + 1)%256
    @q2 = (@q2 + @s[@q1])%256
    @s[@q1], @s[@q2] = @s[@q2], @s[@q1]
    @s[(@s[@q1]+@s[@q2])%256]  
  end

end

puts "Enter key."
    keyInput = gets.chomp
    keyInput = keyInput.to_s
    encryptInstance = Rc4.new(keyInput)
    decryptInstance = Rc4.new(keyInput)

  puts "Enter plaintext."
    plainInput = gets.chomp
    plainInput = plainInput.to_s
    cipherText = encryptInstance.encrypt(plainInput)

  puts "Plaintext is: " + plainInput

  puts "Ciphertext is: " + cipherText

  decryptedText = decryptInstance.encrypt(cipherText)

  puts "Decrypted text is: " + decryptedText

Answer 1

text[i] 在这里是一个字符串。使用text[i].to_i

这应该可以工作

0.upto(text.length-1) {|i| text[i] = (text[i].ord ^ round).chr}

由于您正在进行加密，将“4”转换为 4 将是一个大错误。我们对编码进行操作并将其转换回来。