51CTO学院视频下载和解密
51CTO学院视频m3u8下载和解密
获取课程ID
视频地址
https://edu.51cto.com/center/course/lesson/index?id=394466
394466为课程ID
获取加密的key和m3u8
打开浏览器开发者工具，切换到Network并刷新
获取加密的key
搜索key，会找到一个文件，内容如下，加密key的内容每次都会变化，但是解密得到的key是唯一的
Tim4sMRDywIM0yzUY1zoRG4sOVhpTThJMD0EUVhpZmlpM1iVZk14MjhJMUjlTUwQMDkRVVhpYml1ekjVYUh1RGwsZW0wTTjJYTjFWUy4OXkpMU40YU04emkhYU=I获取m3u8
搜索m3u8，下载m3u8文件，然后将里面的ts文件下载，并进行合并，目前ts视频文件是加密的，无法通过ffmpeg等视频编解码工具进行合并，也无法直接进行播放
解密key
打开Google Chrome的开发者工具，切换到Console，将下面的js代码粘贴进去，按回车键运行
var s = ["s", "i", "y", "u", "a", "n", "t", "l", "w", "x"];
var o = [
function (e) { // index: 0
return e
}
, function (e, t, r) { // index: 1
r = r || "eDu_51Cto_siyuanTlw";
for (var i = base64decode(e).split(""), a = MD5(t + r).toString(), n = a.length - 1; 0 <= n; n--) {
var s = a[n].charCodeAt() % (i.length - 1);
i.splice(s, 1)
}
return i.join("")
}
, function (e, t, r) { // index: 2
for (var i = t % 7, a = e.length, n = "", s = 0; s < a / 2; s++) {
var o = 2 * s;
n += 0 == i || s % i == 0 ? e[o] + e[o + 1] : e[o + 1] ? e[o + 1] + e[o] : e[o]
}
var l = base64decode(n)
, u = (l.length - 1) / 2
, d = "";
for (s = 0; s < u; s++)
o = 2 * s,
i < s && o++ ,
d += s % 3 == 0 ? l[o] : l[o + 1];
return d
}
, function (e) { // index: 3
return e
}
, function (e) { // index: 4
return e
}
, function (e, t, r) { // index: 5
var i, a, n, s, o, l, u, d = e.slice(0, 7) + e.slice(10, 12) + e.slice(15, -3), c = "", h = 0, f = 0, p = "";
d = d.split("").reverse().join(""),
i = eeb64(d),
a = parseInt(i.substr(0, 1)),
s = (n = i.slice(6, -3)).match(/^\d*/),
o = n.match(/\d*$/),
l = s[0],
u = o[0],
n = n.replace(/^\d*/, "").replace(/\d*$/, "");
for (var g = 0; g < u.length; g++)
c += bu(parseInt(u[g]).toString(2), 3);
for (c = c.substr(a),
g = 0; g < c.length; g++)
1 == c[g] ? (p += l[f],
f++) : (p += n[h],
h++);
return p
}
, function (e, t, r) { // index: 6
for (var i, a = {
B: "0",
q: "1",
r: "2",
C: "3",
w: "4",
x: "5",
V: "6",
e: "7",
f: "8",
D: "9",
9: "a",
4: "b",
5: "c",
7: "d",
m: "e",
n: "f",
o: "g",
H: "h",
I: "i",
N: "j",
O: "k",
P: "l",
Q: "m",
R: "n",
S: "o",
U: "p",
X: "q",
L: "r",
M: "s",
a: "t",
b: "u",
F: "v",
c: "w",
d: "x",
g: "y",
h: "z",
i: "A",
j: "B",
y: "C",
z: "D",
k: "E",
l: "F",
6: "G",
G: "H",
A: "I",
p: "J",
s: "K",
t: "L",
u: "M",
J: "N",
K: "O",
v: "P",
W: "Q",
0: "R",
Y: "S",
Z: "T",
2: "U",
3: "V",
E: "W",
T: "X",
8: "Y",
1: "Z"
}, n = 5, s = "", o = 0, l = "", u = 0, d = 0; d < e.length; d++) {
var c = e[d];
s += a[c] ? a[c] : c
}
for (d = 0; d < 8; d++)
i = 7 == d ? 32 - u : Math.abs(8 - n++),
l += s.substr(o++, 1),
o += i,
u += i;
return l += s.substr(40),
eeb64(l.split("").reverse().join(""))
}
, function (e, t, r) { // index: 7
r = r || "eDu_51Cto_siyuanTlw";
var i = eeb64(e)
, a = MD5(r + t).toString().slice(0, 16)
, n = i.indexOf(a)
, s = parseInt(i.slice(0, n), 16);
if (!n)
return !1;
var o = i.substr(16 + n);
return o.length == s && o
}
];
bu = function (e, t) {
for (var r = t - (e += "").length; 0 < r; r--)
e = "0" + e;
return e
}
eeb64 = function (e) {
for (var t = "", r = "", i = 0; i < e.length; i++)
t += bu("BqrCwxVefD9457mnoHINOPQRSUXLMabFcdghijyzkl6GApstuJKvW0YZ23ET81=_".indexOf(e[i]).toString(2), 6);
for (t = t.substring(t.length % 8),
i = 0; i < Math.ceil(t.length / 8); i++)
r += String.fromCharCode(parseInt(t.substr(8 * i, 8), 2));
return base64decode(r)
}
MD5 = function (e) {
var t, a = 0, n = 8;
function o(e, t, r, i, a, n) {
return g((s = g(g(t, e), g(i, n))) << a | s >>> 32 - a, r);
var s
}
function c(e, t, r, i, a, n, s) {
return o(t & r | ~t & i, e, t, a, n, s)
}
function h(e, t, r, i, a, n, s) {
return o(t & i | r & ~i, e, t, a, n, s)
}
function f(e, t, r, i, a, n, s) {
return o(t ^ r ^ i, e, t, a, n, s)
}
function p(e, t, r, i, a, n, s) {
return o(r ^ (t | ~i), e, t, a, n, s)
}
function g(e, t) {
var r = (65535 & e) + (65535 & t);
return (e >> 16) + (t >> 16) + (r >> 16) << 16 | 65535 & r
}
return function (e) {
for (var t = a ? "0123456789ABCDEF" : "0123456789abcdef", r = "", i = 0; i < 4 * e.length; i++)
r += t.charAt(e[i >> 2] >> i % 4 * 8 + 4 & 15) + t.charAt(e[i >> 2] >> i % 4 * 8 & 15);
return r
}(function (e, t) {
e[t >> 5] |= 128 << t % 32,
e[14 + (t + 64 >>> 9 << 4)] = t;
for (var r = 1732584193, i = -271733879, a = -1732584194, n = 271733878, s = 0; s < e.length; s += 16) {
var o = r
, l = i
, u = a
, d = n;
i = p(i = p(i = p(i = p(i = f(i = f(i = f(i = f(i = h(i = h(i = h(i = h(i = c(i = c(i = c(i = c(i, a = c(a, n = c(n, r = c(r, i, a, n, e[s + 0], 7, -680876936), i, a, e[s + 1], 12, -389564586), r, i, e[s + 2], 17, 606105819), n, r, e[s + 3], 22, -1044525330), a = c(a, n = c(n, r = c(r, i, a, n, e[s + 4], 7, -176418897), i, a, e[s + 5], 12, 1200080426), r, i, e[s + 6], 17, -1473231341), n, r, e[s + 7], 22, -45705983), a = c(a, n = c(n, r = c(r, i, a, n, e[s + 8], 7, 1770035416), i, a, e[s + 9], 12, -1958414417), r, i, e[s + 10], 17, -42063), n, r, e[s + 11], 22, -1990404162), a = c(a, n = c(n, r = c(r, i, a, n, e[s + 12], 7, 1804603682), i, a, e[s + 13], 12, -40341101), r, i, e[s + 14], 17, -1502002290), n, r, e[s + 15], 22, 1236535329), a = h(a, n = h(n, r = h(r, i, a, n, e[s + 1], 5, -165796510), i, a, e[s + 6], 9, -1069501632), r, i, e[s + 11], 14, 643717713), n, r, e[s + 0], 20, -373897302), a = h(a, n = h(n, r = h(r, i, a, n, e[s + 5], 5, -701558691), i, a, e[s + 10], 9, 38016083), r, i, e[s + 15], 14, -660478335), n, r, e[s + 4], 20, -405537848), a = h(a, n = h(n, r = h(r, i, a, n, e[s + 9], 5, 568446438), i, a, e[s + 14], 9, -1019803690), r, i, e[s + 3], 14, -187363961), n, r, e[s + 8], 20, 1163531501), a = h(a, n = h(n, r = h(r, i, a, n, e[s + 13], 5, -1444681467), i, a, e[s + 2], 9, -51403784), r, i, e[s + 7], 14, 1735328473), n, r, e[s + 12], 20, -1926607734), a = f(a, n = f(n, r = f(r, i, a, n, e[s + 5], 4, -378558), i, a, e[s + 8], 11, -2022574463), r, i, e[s + 11], 16, 1839030562), n, r, e[s + 14], 23, -35309556), a = f(a, n = f(n, r = f(r, i, a, n, e[s + 1], 4, -1530992060), i, a, e[s + 4], 11, 1272893353), r, i, e[s + 7], 16, -155497632), n, r, e[s + 10], 23, -1094730640), a = f(a, n = f(n, r = f(r, i, a, n, e[s + 13], 4, 681279174), i, a, e[s + 0], 11, -358537222), r, i, e[s + 3], 16, -722521979), n, r, e[s + 6], 23, 76029189), a = f(a, n = f(n, r = f(r, i, a, n, e[s + 9], 4, -640364487), i, a, e[s + 12], 11, -421815835), r, i, e[s + 15], 16, 530742520), n, r, e[s + 2], 23, -995338651), a = p(a, n = p(n, r = p(r, i, a, n, e[s + 0], 6, -198630844), i, a, e[s + 7], 10, 1126891415), r, i, e[s + 14], 15, -1416354905), n, r, e[s + 5], 21, -57434055), a = p(a, n = p(n, r = p(r, i, a, n, e[s + 12], 6, 1700485571), i, a, e[s + 3], 10, -1894986606), r, i, e[s + 10], 15, -1051523), n, r, e[s + 1], 21, -2054922799), a = p(a, n = p(n, r = p(r, i, a, n, e[s + 8], 6, 1873313359), i, a, e[s + 15], 10, -30611744), r, i, e[s + 6], 15, -1560198380), n, r, e[s + 13], 21, 1309151649), a = p(a, n = p(n, r = p(r, i, a, n, e[s + 4], 6, -145523070), i, a, e[s + 11], 10, -1120210379), r, i, e[s + 2], 15, 718787259), n, r, e[s + 9], 21, -343485551),
r = g(r, o),
i = g(i, l),
a = g(a, u),
n = g(n, d)
}
return Array(r, i, a, n)
}(function (e) {
for (var t = Array(), r = (1 << n) - 1, i = 0; i < e.length * n; i += n)
t[i >> 5] |= (e.charCodeAt(i / n) & r) << i % 32;
return t
}(t = e), t.length * n))
}
base64decode = function (e) {
var t, r, i, a, n, s, o, l = new Array(-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1);
for (s = e.length,
n = 0,
o = ""; n < s;) {
for (; t = l[255 & e.charCodeAt(n++)],
n < s && -1 == t;)
;
if (-1 == t)
break;
for (; r = l[255 & e.charCodeAt(n++)],
n < s && -1 == r;)
;
if (-1 == r)
break;
o += String.fromCharCode(t << 2 | (48 & r) >> 4);
do {
if (61 == (i = 255 & e.charCodeAt(n++)))
return o;
i = l[i]
} while (n < s && -1 == i); if (-1 == i)
break;
o += String.fromCharCode((15 & r) << 4 | (60 & i) >> 2);
do {
if (61 == (a = 255 & e.charCodeAt(n++)))
return o;
a = l[a]
} while (n < s && -1 == a); if (-1 == a)
break;
o += String.fromCharCode((3 & i) << 6 | a)
}
return o
}
dec = function (e, t) {
function r(e) {
for (var t = 0; t < s.length; t++)
if (s[t] == e)
return t
}
e[1];
var i = [o[r(e[13])], o[r(e[8])], o[r(e[4])]]
, a = e.substr(0, 1) + e.substr(2, 2) + e.substr(5, 3) + e.substr(9, 4) + e.substr(14);
for (var n in i)
a = i[n](a, t);
return a
}
// 这里的lesson_id就是get-key?lesson_id=1945_324395里的lesson_id
function decode(enKey, lesson_id) {
t = dec(enKey, lesson_id.replace(/_\d*/, ""));
return t;
}
// 和decode的lesson_id相同
function getSign(lesson_id){
let oriralSign = "eDu_51Cto_siyuanTlw";
return MD5(lesson_id + oriralSign).toString();
}然后在Console中执行以下代码，对加密的key进行解密
//decode("加密key","lesson_id")
decode("Tim4sMRDywIM0yzUY1zoRG4sOVhpTThJMD0EUVhpZmlpM1iVZk14MjhJMUjlTUwQMDkRVVhpYml1ekjVYUh1RGwsZW0wTTjJYTjFWUy4OXkpMU40YU04emkhYU=I","394466")得到解密的key如下
4ddd57b5fa93f370使用openssl解密视频，需要先把解密key转为32位的16进制字符串
可以通过这个在线工具https://www.bejson.com/convert/ox2str/
转换后得到
34646464353762356661393366333730解密视频
使用openssl对视频进行解密，执行以下命令
openssl aes-128-ecb -d -in "1.ts" -out "2.ts" -K 34646464353762356661393366333730-in 为加密视频文件名
-out 为解密视频文件名
-K 为上一步转换后得到的key
来源：
https://www.cnblogs.com/QIAOXINGXING001/p/12318011.html
https://www.52pojie.cn/thread-1109031-1-1.html