注意！！！！某数据网站逆向实例仅作为学习案例，禁止其他个人以及团体做谋利用途！！！！

案例分析

第一步：分析页面。查看响应内容，内容加密

 第二步：检索“encrypt_data”此网站有6个被检索到，但是其他都含有 img不符合要求，只有一个复核，在此处打断点。

 第三步：查看加密内容被哪个函数作为参数传入。将鼠标放在“d.a”处会出现该函数名以及所在位置。

第四步： 将此处代码复制出来。同时发现 “o”函数和“a.a.decode”函数未在该函数中。需要进行查找

 第五步：“o”函数

 第六步：“a.a.decode”函数。注意！！！decoed : function(t)....不符合，将代码扣下在本地执行的要求需要改写。详情见代码

 最后：代码实现

JS 部分代码

注意！！！js 代码从浏览器到本地，本地执行时缺什么参数回浏览器里找，以及本地补充环境

function s(e) {
    return JSON.parse(o("5e5062e82f15fe4ca9d24bc5", decode_gaixie(e), 0, 0, "012345677890123", 1))
}

function o(e, t, i, n, a, o) {
    var s, c, r, l, d, u, h, p, f, m, v, g, y, b,
        C = new Array(16843776, 0, 65536, 16843780, 16842756, 66564, 4, 65536, 1024, 16843776, 16843780, 1024, 16778244, 16842756, 16777216, 4, 1028, 16778240, 16778240, 66560, 66560, 16842752, 16842752, 16778244, 65540, 16777220, 16777220, 65540, 0, 1028, 66564, 16777216, 65536, 16843780, 4, 16842752, 16843776, 16777216, 16777216, 1024, 16842756, 65536, 66560, 16777220, 1024, 4, 16778244, 66564, 16843780, 65540, 16842752, 16778244, 16777220, 1028, 66564, 16843776, 1028, 16778240, 16778240, 0, 65540, 66560, 0, 16842756),
        _ = new Array(-2146402272, -2147450880, 32768, 1081376, 1048576, 32, -2146435040, -2147450848, -2147483616, -2146402272, -2146402304, -2147483648, -2147450880, 1048576, 32, -2146435040, 1081344, 1048608, -2147450848, 0, -2147483648, 32768, 1081376, -2146435072, 1048608, -2147483616, 0, 1081344, 32800, -2146402304, -2146435072, 32800, 0, 1081376, -2146435040, 1048576, -2147450848, -2146435072, -2146402304, 32768, -2146435072, -2147450880, 32, -2146402272, 1081376, 32, 32768, -2147483648, 32800, -2146402304, 1048576, -2147483616, 1048608, -2147450848, -2147483616, 1048608, 1081344, 0, -2147450880, 32800, -2147483648, -2146435040, -2146402272, 1081344),
        w = new Array(520, 134349312, 0, 134348808, 134218240, 0, 131592, 134218240, 131080, 134217736, 134217736, 131072, 134349320, 131080, 134348800, 520, 134217728, 8, 134349312, 512, 131584, 134348800, 134348808, 131592, 134218248, 131584, 131072, 134218248, 8, 134349320, 512, 134217728, 134349312, 134217728, 131080, 520, 131072, 134349312, 134218240, 0, 512, 131080, 134349320, 134218240, 134217736, 512, 0, 134348808, 134218248, 131072, 134217728, 134349320, 8, 131592, 131584, 134217736, 134348800, 134218248, 520, 134348800, 131592, 8, 134348808, 131584),
        k = new Array(8396801, 8321, 8321, 128, 8396928, 8388737, 8388609, 8193, 0, 8396800, 8396800, 8396929, 129, 0, 8388736, 8388609, 1, 8192, 8388608, 8396801, 128, 8388608, 8193, 8320, 8388737, 1, 8320, 8388736, 8192, 8396928, 8396929, 129, 8388736, 8388609, 8396800, 8396929, 129, 0, 0, 8396800, 8320, 8388736, 8388737, 1, 8396801, 8321, 8321, 128, 8396929, 129, 1, 8192, 8388609, 8193, 8396928, 8388737, 8193, 8320, 8388608, 8396801, 128, 8388608, 8192, 8396928),
        x = new Array(256, 34078976, 34078720, 1107296512, 524288, 256, 1073741824, 34078720, 1074266368, 524288, 33554688, 1074266368, 1107296512, 1107820544, 524544, 1073741824, 33554432, 1074266112, 1074266112, 0, 1073742080, 1107820800, 1107820800, 33554688, 1107820544, 1073742080, 0, 1107296256, 34078976, 33554432, 1107296256, 524544, 524288, 1107296512, 256, 33554432, 1073741824, 34078720, 1107296512, 1074266368, 33554688, 1073741824, 1107820544, 34078976, 1074266368, 256, 33554432, 1107820544, 1107820800, 524544, 1107296256, 1107820800, 34078720, 0, 1074266112, 1107296256, 524544, 33554688, 1073742080, 524288, 0, 1074266112, 34078976, 1073742080),
        T = new Array(536870928, 541065216, 16384, 541081616, 541065216, 16, 541081616, 4194304, 536887296, 4210704, 4194304, 536870928, 4194320, 536887296, 536870912, 16400, 0, 4194320, 536887312, 16384, 4210688, 536887312, 16, 541065232, 541065232, 0, 4210704, 541081600, 16400, 4210688, 541081600, 536870912, 536887296, 16, 541065232, 4210688, 541081616, 4194304, 16400, 536870928, 4194304, 536887296, 536870912, 16400, 536870928, 541081616, 4210688, 541065216, 4210704, 541081600, 0, 541065232, 16, 16384, 541065216, 4210704, 16384, 4194320, 536887312, 0, 541081600, 536870912, 4194320, 536887312),
        A = new Array(2097152, 69206018, 67110914, 0, 2048, 67110914, 2099202, 69208064, 69208066, 2097152, 0, 67108866, 2, 67108864, 69206018, 2050, 67110912, 2099202, 2097154, 67110912, 67108866, 69206016, 69208064, 2097154, 69206016, 2048, 2050, 69208066, 2099200, 2, 67108864, 2099200, 67108864, 2099200, 2097152, 67110914, 67110914, 69206018, 69206018, 2, 2097154, 67108864, 67110912, 2097152, 69208064, 2050, 2099202, 69208064, 2050, 67108866, 69208066, 69206016, 2099200, 0, 2, 69208066, 0, 2099202, 69206016, 2048, 67108866, 67110912, 2048, 2097154),
        N = new Array(268439616, 4096, 262144, 268701760, 268435456, 268439616, 64, 268435456, 262208, 268697600, 268701760, 266240, 268701696, 266304, 4096, 64, 268697600, 268435520, 268439552, 4160, 266240, 262208, 268697664, 268701696, 4160, 0, 0, 268697664, 268435520, 268439552, 266304, 262144, 266304, 262144, 268701696, 4096, 64, 268697664, 4096, 266304, 268439552, 64, 268435520, 268697600, 268697664, 268435456, 262144, 268439616, 0, 268701760, 262208, 268435520, 268697600, 268439552, 268439616, 0, 268701760, 266240, 266240, 4160, 4160, 262208, 268435456, 268701696),
        $ = function (e) {
            for (var t, i, n, a = new Array(0, 4, 536870912, 536870916, 65536, 65540, 536936448, 536936452, 512, 516, 536871424, 536871428, 66048, 66052, 536936960, 536936964), o = new Array(0, 1, 1048576, 1048577, 67108864, 67108865, 68157440, 68157441, 256, 257, 1048832, 1048833, 67109120, 67109121, 68157696, 68157697), s = new Array(0, 8, 2048, 2056, 16777216, 16777224, 16779264, 16779272, 0, 8, 2048, 2056, 16777216, 16777224, 16779264, 16779272), c = new Array(0, 2097152, 134217728, 136314880, 8192, 2105344, 134225920, 136323072, 131072, 2228224, 134348800, 136445952, 139264, 2236416, 134356992, 136454144), r = new Array(0, 262144, 16, 262160, 0, 262144, 16, 262160, 4096, 266240, 4112, 266256, 4096, 266240, 4112, 266256), l = new Array(0, 1024, 32, 1056, 0, 1024, 32, 1056, 33554432, 33555456, 33554464, 33555488, 33554432, 33555456, 33554464, 33555488), d = new Array(0, 268435456, 524288, 268959744, 2, 268435458, 524290, 268959746, 0, 268435456, 524288, 268959744, 2, 268435458, 524290, 268959746), u = new Array(0, 65536, 2048, 67584, 536870912, 536936448, 536872960, 536938496, 131072, 196608, 133120, 198656, 537001984, 537067520, 537004032, 537069568), h = new Array(0, 262144, 0, 262144, 2, 262146, 2, 262146, 33554432, 33816576, 33554432, 33816576, 33554434, 33816578, 33554434, 33816578), p = new Array(0, 268435456, 8, 268435464, 0, 268435456, 8, 268435464, 1024, 268436480, 1032, 268436488, 1024, 268436480, 1032, 268436488), f = new Array(0, 32, 0, 32, 1048576, 1048608, 1048576, 1048608, 8192, 8224, 8192, 8224, 1056768, 1056800, 1056768, 1056800), m = new Array(0, 16777216, 512, 16777728, 2097152, 18874368, 2097664, 18874880, 67108864, 83886080, 67109376, 83886592, 69206016, 85983232, 69206528, 85983744), v = new Array(0, 4096, 134217728, 134221824, 524288, 528384, 134742016, 134746112, 16, 4112, 134217744, 134221840, 524304, 528400, 134742032, 134746128), g = new Array(0, 4, 256, 260, 0, 4, 256, 260, 1, 5, 257, 261, 1, 5, 257, 261), y = e.length > 8 ? 3 : 1, b = new Array(32 * y), C = new Array(0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0), _ = 0, w = 0, k = 0; k < y; k++) {
                var x = e.charCodeAt(_++) << 24 | e.charCodeAt(_++) << 16 | e.charCodeAt(_++) << 8 | e.charCodeAt(_++)
                    ,
                    T = e.charCodeAt(_++) << 24 | e.charCodeAt(_++) << 16 | e.charCodeAt(_++) << 8 | e.charCodeAt(_++);
                x ^= (n = 252645135 & (x >>> 4 ^ T)) << 4,
                    x ^= n = 65535 & ((T ^= n) >>> -16 ^ x),
                    x ^= (n = 858993459 & (x >>> 2 ^ (T ^= n << -16))) << 2,
                    x ^= n = 65535 & ((T ^= n) >>> -16 ^ x),
                    x ^= (n = 1431655765 & (x >>> 1 ^ (T ^= n << -16))) << 1,
                    x ^= n = 16711935 & ((T ^= n) >>> 8 ^ x),
                    n = (x ^= (n = 1431655765 & (x >>> 1 ^ (T ^= n << 8))) << 1) << 8 | (T ^= n) >>> 20 & 240,
                    x = T << 24 | T << 8 & 16711680 | T >>> 8 & 65280 | T >>> 24 & 240,
                    T = n;
                for (var A = 0; A < C.length; A++)
                    C[A] ? (x = x << 2 | x >>> 26,
                        T = T << 2 | T >>> 26) : (x = x << 1 | x >>> 27,
                        T = T << 1 | T >>> 27),
                        T &= -15,
                        t = a[(x &= -15) >>> 28] | o[x >>> 24 & 15] | s[x >>> 20 & 15] | c[x >>> 16 & 15] | r[x >>> 12 & 15] | l[x >>> 8 & 15] | d[x >>> 4 & 15],
                        i = u[T >>> 28] | h[T >>> 24 & 15] | p[T >>> 20 & 15] | f[T >>> 16 & 15] | m[T >>> 12 & 15] | v[T >>> 8 & 15] | g[T >>> 4 & 15],
                        n = 65535 & (i >>> 16 ^ t),
                        b[w++] = t ^ n,
                        b[w++] = i ^ n << 16
            }
            return b
        }(e), L = 0, S = t.length, z = 0, I = 32 == $.length ? 3 : 9;
    p = 3 == I ? i ? new Array(0, 32, 2) : new Array(30, -2, -2) : i ? new Array(0, 32, 2, 62, 30, -2, 64, 96, 2) : new Array(94, 62, -2, 32, 64, 2, 30, -2, -2),
        2 == o ? t += "        " : 1 == o ? i && (r = 8 - S % 8,
            t += String.fromCharCode(r, r, r, r, r, r, r, r),
        8 === r && (S += 8)) : o || (t += "\0\0\0\0\0\0\0\0");
    var B = ""
        , F = "";
    for (1 == n && (f = a.charCodeAt(L++) << 24 | a.charCodeAt(L++) << 16 | a.charCodeAt(L++) << 8 | a.charCodeAt(L++),
        v = a.charCodeAt(L++) << 24 | a.charCodeAt(L++) << 16 | a.charCodeAt(L++) << 8 | a.charCodeAt(L++),
        L = 0); L < S;) {
        for (u = t.charCodeAt(L++) << 24 | t.charCodeAt(L++) << 16 | t.charCodeAt(L++) << 8 | t.charCodeAt(L++),
                 h = t.charCodeAt(L++) << 24 | t.charCodeAt(L++) << 16 | t.charCodeAt(L++) << 8 | t.charCodeAt(L++),
             1 == n && (i ? (u ^= f,
                 h ^= v) : (m = f,
                 g = v,
                 f = u,
                 v = h)),
                 u ^= (r = 252645135 & (u >>> 4 ^ h)) << 4,
                 u ^= (r = 65535 & (u >>> 16 ^ (h ^= r))) << 16,
                 u ^= r = 858993459 & ((h ^= r) >>> 2 ^ u),
                 u ^= r = 16711935 & ((h ^= r << 2) >>> 8 ^ u),
                 u = (u ^= (r = 1431655765 & (u >>> 1 ^ (h ^= r << 8))) << 1) << 1 | u >>> 31,
                 h = (h ^= r) << 1 | h >>> 31,
                 c = 0; c < I; c += 3) {
            for (y = p[c + 1],
                     b = p[c + 2],
                     s = p[c]; s != y; s += b)
                l = h ^ $[s],
                    d = (h >>> 4 | h << 28) ^ $[s + 1],
                    r = u,
                    u = h,
                    h = r ^ (_[l >>> 24 & 63] | k[l >>> 16 & 63] | T[l >>> 8 & 63] | N[63 & l] | C[d >>> 24 & 63] | w[d >>> 16 & 63] | x[d >>> 8 & 63] | A[63 & d]);
            r = u,
                u = h,
                h = r
        }
        h = h >>> 1 | h << 31,
            h ^= r = 1431655765 & ((u = u >>> 1 | u << 31) >>> 1 ^ h),
            h ^= (r = 16711935 & (h >>> 8 ^ (u ^= r << 1))) << 8,
            h ^= (r = 858993459 & (h >>> 2 ^ (u ^= r))) << 2,
            h ^= r = 65535 & ((u ^= r) >>> 16 ^ h),
            h ^= r = 252645135 & ((u ^= r << 16) >>> 4 ^ h),
            u ^= r << 4,
        1 == n && (i ? (f = u,
            v = h) : (u ^= m,
            h ^= g)),
            F += String.fromCharCode(u >>> 24, u >>> 16 & 255, u >>> 8 & 255, 255 & u, h >>> 24, h >>> 16 & 255, h >>> 8 & 255, 255 & h),
        512 == (z += 8) && (B += F,
            F = "",
            z = 0)
    }
    if (B = (B += F).replace(/\0*$/g, ""),
        !i) {
        if (1 === o) {
            var j = 0;
            (S = B.length) && (j = B.charCodeAt(S - 1)),
            j <= 8 && (B = B.substring(0, S - j))
        }
        B = decodeURIComponent(escape(B))
    }
    return B
}

function decode_gaixie(t) {
    var f = '/[\\t\\n\\f\\r ]/g';
    var l = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
    var e = (t = String(t).replace(f, "")).length;
    e % 4 == 0 && (e = (t = t.replace(/==?$/, "")).length),
    (e % 4 == 1 || /[^+a-zA-Z0-9/]/.test(t)) && u("Invalid character: the string to be decoded is not correctly encoded.");
    for (var n, r, i = 0, o = "", a = -1; ++a < e;)
        r = l.indexOf(t.charAt(a)),
            n = i % 4 ? 64 * n + r : r,
        i++ % 4 && (o += String.fromCharCode(255 & n >> (-2 * i & 6)));
    return o
}

 Python部分代码

# 安装 execjs 可执行 pip install pyexecjs2
import execjs
encrypt_data = ''    # 加密内容 自行请求可得
with open('./企名片-js.js','r', encoding='utf-8') as f:
    js_code = f.read()
ctx = execjs.compile(js_code)
result = ctx.call("s",encrypt_data)
print(result)

 仅作为笔记记录，如有问题请各位大佬来指导