一、混沌语音加密简介

语音的数据安全是网络语音通信的重要问题之一,混沌序列由于具有类随机性常被用作加密密钥。

二、部分源代码

clear all
close all
clc
%%
%aes加密
%利用密钥定义S盒
keyh = {'2b' '7e' '15' '16' '28' 'ae' 'd2' 'a6'...
    'ab' 'f7' '15' '88' '09' 'cf' '4f' '3c'};
key = hex2dec(keyh);
s = aesinit(key);
%切分语音矩阵
x=audioread('s.wav');
x7=ceil(100*x(:,2))+127;
n=floor(length(x7)/16);
for i=1:n
    eval(['x',num2str(i+7),'=','x7(',num2str((i-1)*16+1),':',num2str(i*16),');'])
    eval(['ct',num2str(i),'=','aesjiami(s,x',num2str(i+7),');'])
    eval(['pt',num2str(i),'=','aesjiemi(s,ct',num2str(i),');'])
end
ct=[];
pt=[];
for i=1:n
    eval(['ct=[ct ct',num2str(i),'];'])
    eval(['pt=[pt pt',num2str(i),'];'])
end
t=(0:16*n-1)/8000;
figure(6)
subplot(3,1,1);
plot(t,x7(1:16*n))%原始语音信号
grid on;
axis tight;
title('原始语音信号');
xlabel('time(s)');
ylabel('幅度');
subplot(3,1,2);
plot(t,ct)%加密语音信号
grid on;
axis tight;
title('加密语音信号');
xlabel('time(s)');
ylabel('幅度');
subplot(3,1,3);
plot(t,pt)%加密语音信号
grid on;
axis tight;
title('解密语音信号');
xlabel('time(s)');
ylabel('幅度');
function [output] = aes(s, oper, mode, input, iv, sbit)
% AES 加密/解密矩阵处理
% output = aes(s, oper, mode, input, iv, sbit)
% 加密/解密密钥标准：AES-128, AES-192, AES-256.
% NIST SP800-38A标准的密钥都可以适用(e.g. ECB, CBC, OFB, CFB, CTR).
% 解密例子:         out = aesdecrypt(s, 'dec', 'ecb', data)
% s:                AES结构(由aesinit产生)
% oper:             操作选项:
%                   'e', 'enc', 'encrypt', 'E',... = encrypt加密
%                   'd', 'dec', 'decrypt', 'D',... = decrypt解密
% mode:             操作模式
%                   'ecb' = Electronic Codebook Mode电子密码本模式
%                   'cbc' = Cipher Block Chaining Mode密码块链接模式
%                   'cfb' = Cipher Feedback Mode密码反馈方式, 加密回馈模式
%                   'ofb' = Output Feedback Mode输出反馈模式
%                   'ctr' = Counter Mode计数器模式
%                   如需要使用counter mode，则使用另一函数AES_GET_COUNTER()
% input:            16位明文/密文
% iv:               初始化向量
% sbit:             CFB模式的参数长度
% output:           输出密文/明文
%
% 参考文献：
% Morris Dworkin, Recommendation for Block Cipher Modes of Operation
% Methods and Techniques
% NIST Special Publication 800-38A, 2001 Edition

error(nargchk(4, 6, nargin));

validateattributes(s, {'struct'}, {});
validateattributes(oper, {'char'}, {});
validateattributes(mode, {'char'}, {});
validateattributes(input, {'numeric'}, {'real', 'vector', '>=', 0, '<', 256});
if (nargin >= 5)
    validateattributes(iv, {'numeric'}, {'real', 'vector', '>=', 0, '<', 256});
    if (length(iv) ~= 16)
        error('Length of ''iv'' must be 16.');
    end
end
if (nargin >= 6)
    validateattributes(sbit, {'numeric'}, {'real', 'scalar', '>=', 1, '<=', 128});
end

if (mod(length(input), 16))
    error('Length of ''input'' must be multiple of 16.');
end

switch lower(oper)
    case {'encrypt', 'enc', 'e'}
        oper = 0;
    case {'decrypt', 'dec', 'd'}
        oper = 1;
    otherwise
        error('Bad ''oper'' parameter.');
end

blocks = length(input)/16;
input = input(:);

switch lower(mode)

    case {'ecb'}
        % Electronic Codebook Mode
        % ------------------------
        output = zeros(1,length(input));
        idx = 1:16;
        for i = 1:blocks
            if (oper)
                % 解密
                output(idx) = aesdecrypt(s,input(idx));
            else
                % 加密
                output(idx) = aesencrypt(s,input(idx));
            end
            idx = idx + 16;
        end
        
    case {'cbc'}
        % Cipher Block Chaining Mode
        % --------------------------
        if (nargin < 5)
            error('Missing initialization vector ''iv''.');
        end
        output = zeros(1,length(input));
        ob = iv;
        idx = 1:16;
        for i = 1:blocks
            if (oper)
                % 解密
                in = input(idx);
                output(idx) = bitxor(ob(:), aesdecrypt(s,in)');
                ob = in;
            else
                % 加密
                ob = bitxor(ob(:), input(idx));
                ob = aesencrypt(s, ob);
                output(idx) = ob;
            end
            idx = idx + 16;
        end
        % 储存用于块传递的iv
        s.iv = ob;
        
    case {'cfb'}
        % Cipher Feedback Mode
        if (nargin < 6)
            error('Missing ''sbit'' parameter.');
        end
        % 读取输入明文/密文的长度
        bitlen = 8*length(input);
        % 循环计数器
        rounds = round(bitlen/sbit);
        % 检测错误 
        if (rem(bitlen, sbit))
            error('Message length in bits is not multiple of ''sbit''.');
        end
        % 将输入转换为比特流
        inputb = reshape(de2bi(input,8,2,'left-msb')',1,bitlen);
        % 预设init
        ib = iv;
        ibb = reshape(de2bi(ib,8,2,'left-msb')',1,128);
        % 预设输出二进制流
        outputb = zeros(size(inputb));
        for i = 1:rounds
            iba = aesencrypt(s, ib);
            % 移位
            ibab = reshape(de2bi(iba,8,2,'left-msb')',1,128);
            ibab = ibab(1:sbit);
            inpb = inputb((i - 1)*sbit + (1:sbit));
            outb = bitxor(ibab, inpb);
            outputb((i - 1)*sbit + (1:sbit)) = outb;
            if (oper)
                % 解密
                % 定义新移位方式
                ibb = [ibb((1 + sbit):end) inpb];
            else
                % 加密
                ibb = [ibb((1 + sbit):end) outb];
            end
            % 返回字节
            ib = bi2de(vec2mat(ibb,8),'left-msb');
            % 循环
        end
        output = bi2de(vec2mat(outputb,8),'left-msb');
        % 储存用于块传递的iv
        s.iv = ib;
        
   
        
    case {'ctr'}
        % Counter Mode
        if (nargin < 5)
            iv = 1;
        end
        output = zeros(1,length(input));
        idx = 1:16;
        for i = (iv):(iv + blocks - 1)
            ib = AES_GET_COUNTER(i);
            ib = aesencrypt(s, ib);
            output(idx) = bitxor(ib(:), input(idx));
            idx = idx + 16;
        end
        s.iv = iv + blocks;
        
    otherwise
        error('Bad ''oper'' parameter.');
end

三、运行结果

四、matlab版本及参考文献

1 matlab版本
2014a

2 参考文献
[1]韩纪庆,张磊,郑铁然.语音信号处理（第3版）[M].清华大学出版社，2019.
[2]柳若边.深度学习:语音识别技术实践[M].清华大学出版社，2019.
[3]葛秀梅,仲伟波,李忠梅,范东升.基于DSP的混沌语音加密解密系统[J].实验室研究与探索. 2014,33(09)