Usually when we test logical vulnerabilities or write crawlers, if we encounter front-end encryption, we can choose to drag out the encryption algorithm and encrypt the parameters we debug.Copy the code

MD5 Encryption instance

Login test, get the POST parameter
Break at suspected point and send packet again
Check that the value here is the same as the encrypted value, so this is the encryption algorithm
This is a closure function that implements the encryption algorithm

Here can directly use MD5 encryption test, but does not rule out it named MD5 (), in fact, their own implementation of the encryption algorithm.

(function(g) {
function o(u, z) {
var w = (u & 65535) + (z & 65535)
, v = (u >> 16) + (z >> 16) + (w >> 16);
return (v << 16) | (w & 65535)
}
function s(u, v) {
return (u << v) | (u >>> (32 - v))
}
function c(A, w, v, u, z, y) {
return o(s(o(o(w, A), o(u, y)), z), v)
}
function b(w, v, B, A, u, z, y) {
return c((v & B) | ((~v) & A), w, v, u, z, y)
}
function i(w, v, B, A, u, z, y) {
return c((v & A) | (B & (~A)), w, v, u, z, y)
}
function n(w, v, B, A, u, z, y) {
return c(v ^ B ^ A, w, v, u, z, y)
}
function a(w, v, B, A, u, z, y) {
return c(B ^ (v | (~A)), w, v, u, z, y)
}
function d(F, A) {
F[A >> 5] |= 128 << ((A) % 32);
F[(((A + 64) >>> 9) << 4) + 14] = A;
var w, z, y, v, u, E = 1732584193, D = -271733879, C = -1732584194, B = 271733878;
for (w = 0; w < F.length; w += 16) {
z = E;
y = D;
v = C;
u = B;
E = b(E, D, C, B, F[w], 7, -680876936);
B = b(B, E, D, C, F[w + 1], 12, -389564586);
C = b(C, B, E, D, F[w + 2], 17, 606105819);
D = b(D, C, B, E, F[w + 3], 22, -1044525330);
E = b(E, D, C, B, F[w + 4], 7, -176418897);
B = b(B, E, D, C, F[w + 5], 12, 1200080426);
C = b(C, B, E, D, F[w + 6], 17, -1473231341);
D = b(D, C, B, E, F[w + 7], 22, -45705983);
E = b(E, D, C, B, F[w + 8], 7, 1770035416);
B = b(B, E, D, C, F[w + 9], 12, -1958414417);
C = b(C, B, E, D, F[w + 10], 17, -42063);
D = b(D, C, B, E, F[w + 11], 22, -1990404162);
E = b(E, D, C, B, F[w + 12], 7, 1804603682);
B = b(B, E, D, C, F[w + 13], 12, -40341101);
C = b(C, B, E, D, F[w + 14], 17, -1502002290);
D = b(D, C, B, E, F[w + 15], 22, 1236535329);
E = i(E, D, C, B, F[w + 1], 5, -165796510);
B = i(B, E, D, C, F[w + 6], 9, -1069501632);
C = i(C, B, E, D, F[w + 11], 14, 643717713);
D = i(D, C, B, E, F[w], 20, -373897302);
E = i(E, D, C, B, F[w + 5], 5, -701558691);
B = i(B, E, D, C, F[w + 10], 9, 38016083);
C = i(C, B, E, D, F[w + 15], 14, -660478335);
D = i(D, C, B, E, F[w + 4], 20, -405537848);
E = i(E, D, C, B, F[w + 9], 5, 568446438);
B = i(B, E, D, C, F[w + 14], 9, -1019803690);
C = i(C, B, E, D, F[w + 3], 14, -187363961);
D = i(D, C, B, E, F[w + 8], 20, 1163531501);
E = i(E, D, C, B, F[w + 13], 5, -1444681467);
B = i(B, E, D, C, F[w + 2], 9, -51403784);
C = i(C, B, E, D, F[w + 7], 14, 1735328473);
D = i(D, C, B, E, F[w + 12], 20, -1926607734);
E = n(E, D, C, B, F[w + 5], 4, -378558);
B = n(B, E, D, C, F[w + 8], 11, -2022574463);
C = n(C, B, E, D, F[w + 11], 16, 1839030562);
D = n(D, C, B, E, F[w + 14], 23, -35309556);
E = n(E, D, C, B, F[w + 1], 4, -1530992060);
B = n(B, E, D, C, F[w + 4], 11, 1272893353);
C = n(C, B, E, D, F[w + 7], 16, -155497632);
D = n(D, C, B, E, F[w + 10], 23, -1094730640);
E = n(E, D, C, B, F[w + 13], 4, 681279174);
B = n(B, E, D, C, F[w], 11, -358537222);
C = n(C, B, E, D, F[w + 3], 16, -722521979);
D = n(D, C, B, E, F[w + 6], 23, 76029189);
E = n(E, D, C, B, F[w + 9], 4, -640364487);
B = n(B, E, D, C, F[w + 12], 11, -421815835);
C = n(C, B, E, D, F[w + 15], 16, 530742520);
D = n(D, C, B, E, F[w + 2], 23, -995338651);
E = a(E, D, C, B, F[w], 6, -198630844);
B = a(B, E, D, C, F[w + 7], 10, 1126891415);
C = a(C, B, E, D, F[w + 14], 15, -1416354905);
D = a(D, C, B, E, F[w + 5], 21, -57434055);
E = a(E, D, C, B, F[w + 12], 6, 1700485571);
B = a(B, E, D, C, F[w + 3], 10, -1894986606);
C = a(C, B, E, D, F[w + 10], 15, -1051523);
D = a(D, C, B, E, F[w + 1], 21, -2054922799);
E = a(E, D, C, B, F[w + 8], 6, 1873313359);
B = a(B, E, D, C, F[w + 15], 10, -30611744);
C = a(C, B, E, D, F[w + 6], 15, -1560198380);
D = a(D, C, B, E, F[w + 13], 21, 1309151649);
E = a(E, D, C, B, F[w + 4], 6, -145523070);
B = a(B, E, D, C, F[w + 11], 10, -1120210379);
C = a(C, B, E, D, F[w + 2], 15, 718787259);
D = a(D, C, B, E, F[w + 9], 21, -343485551);
E = o(E, z);
D = o(D, y);
C = o(C, v);
B = o(B, u)
}
return [E, D, C, B]
}
function p(v) {
var w, u = "";
for (w = 0; w < v.length * 32; w += 8) {
u += String.fromCharCode((v[w >> 5] >>> (w % 32)) & 255)
}
return u
}
function j(v) {
var w, u = [];
u[(v.length >> 2) - 1] = undefined;
for (w = 0; w < u.length; w += 1) {
u[w] = 0
}
for (w = 0; w < v.length * 8; w += 8) {
u[w >> 5] |= (v.charCodeAt(w / 8) & 255) << (w % 32)
}
return u
}
function k(u) {
return p(d(j(u), u.length * 8))
}
function f(w, z) {
var v, y = j(w), u = [], x = [], A;
u[15] = x[15] = undefined;
if (y.length > 16) {
y = d(y, w.length * 8)
}
for (v = 0; v < 16; v += 1) {
u[v] = y[v] ^ 909522486;
x[v] = y[v] ^ 1549556828
}
A = d(u.concat(j(z)), 512 + z.length * 8);
return p(d(x.concat(A), 512 + 128))
}
function t(w) {
var z = "0123456789abcdef", v = "", u, y;
for (y = 0; y < w.length; y += 1) {
u = w.charCodeAt(y);
v += z.charAt((u >>> 4) & 15) + z.charAt(u & 15)
}
return v
}
function m(u) {
return unescape(encodeURIComponent(u))
}
function q(u) {
return k(m(u))
}
function l(u) {
return t(q(u))
}
function h(u, v) {
return f(m(u), m(v))
}
function r(u, v) {
return t(h(u, v))
}
g.md5 = function(v, w, u) {
if (!w) {
if (!u) {
return l(v)
} else {
return q(v)
}
}
if (!u) {
return r(w, v)
} else {
return h(w, v)
}
}
}(typeof jQuery === "function" ? jQuery : this));
Copy the code

2021 full set of network security information package and the latest interview questions (penetration tools, environment building, HTML, PHP, MySQL basic learning, information collection, SQL injection,XSS, CSRF, brute force cracking, etc.)

Debug this code

Python implementation

RSA Asymmetric key encryption instance

Log in contract
Suspected point downbreak

Search encryption algorithm

Encryption algorithm implementation and debugging

var RSAPublicKey = function($modulus_hex, $encryptionExponent_hex) { this.modulus = new BigInteger( $modulus_hex, 16); this.encryptionExponent = new BigInteger( $encryptionExponent_hex, 16); }; var Base64 = { base64: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", encode: function($input) { if (! $input) { return false; } var $output = ""; var $chr1, $chr2, $chr3; var $enc1, $enc2, $enc3, $enc4; var $i = 0; do { $chr1 = $input.charCodeAt($i++); $chr2 = $input.charCodeAt($i++); $chr3 = $input.charCodeAt($i++); $enc1 = $chr1 >> 2; $enc2 = (($chr1 & 3) << 4) | ($chr2 >> 4); $enc3 = (($chr2 & 15) << 2) | ($chr3 >> 6); $enc4 = $chr3 & 63; if (isNaN($chr2)) $enc3 = $enc4 = 64; else if (isNaN($chr3)) $enc4 = 64; $output += this.base64.charAt($enc1) + this.base64.charAt($enc2) + this.base64.charAt($enc3) + this.base64.charAt($enc4); } while ($i < $input.length); return $output; }, decode: function($input) { if(! $input) return false; $input = $input.replace(/[^A-Za-z0-9+/=]/g, ""); var $output = ""; var $enc1, $enc2, $enc3, $enc4; var $i = 0; do { $enc1 = this.base64.indexOf($input.charAt($i++)); $enc2 = this.base64.indexOf($input.charAt($i++)); $enc3 = this.base64.indexOf($input.charAt($i++)); $enc4 = this.base64.indexOf($input.charAt($i++)); $output += String.fromCharCode(($enc1 << 2) | ($enc2 >> 4)); if ($enc3 ! = 64) $output += String.fromCharCode((($enc2 & 15) << 4) | ($enc3 >> 2)); if ($enc4 ! = 64) $output += String.fromCharCode((($enc3 & 3) << 6) | $enc4); } while ($i < $input.length); return $output; }}; var Hex = { hex: "0123456789abcdef", encode: function($input) { if(! $input) return false; var $output = ""; var $k; var $i = 0; do { $k = $input.charCodeAt($i++); $output += this.hex.charAt(($k >> 4) &0xf) + this.hex.charAt($k & 0xf); } while ($i < $input.length); return $output; }, decode: function($input) { if(! $input) return false; $input = $input.replace(/[^0-9abcdef]/g, ""); var $output = ""; var $i = 0; do { $output += String.fromCharCode(((this.hex.indexOf($input.charAt($i++)) << 4) & 0xf0) | (this.hex.indexOf($input.charAt($i++)) & 0xf)); } while ($i < $input.length); return $output; }};Copy the code

BigInteger is undefined, find this function implementation and paste it

function bnpCopyTo(r) { for(var i = this.t-1; i >= 0; --i) r[i] = this[i]; r.t = this.t; r.s = this.s; } // (protected) set from integer value x, -DV <= x < DV function bnpFromInt(x) { this.t = 1; this.s = (x<0)? - 1-0. if(x > 0) this[0] = x; else if(x < -1) this[0] = x+DV; else this.t = 0; } // return bigint initialized to value function nbv(i) { var r = nbi(); r.fromInt(i); return r; } // (protected) set from string and radix function bnpFromString(s,b) { var k; if(b == 16) k = 4; else if(b == 8) k = 3; else if(b == 256) k = 8; // byte array else if(b == 2) k = 1; else if(b == 32) k = 5; else if(b == 4) k = 2; else { this.fromRadix(s,b); return; } this.t = 0; this.s = 0; var i = s.length, mi = false, sh = 0; while(--i >= 0) { var x = (k==8)? s[i]&0xff:intAt(s,i); if(x < 0) { if(s.charAt(i) == "-") mi = true; continue; } mi = false; if(sh == 0) this[this.t++] = x; else if(sh+k > this.DB) { this[this.t-1] |= (x&((1<<(this.DB-sh))-1))<<sh; this[this.t++] = (x>>(this.DB-sh)); } else this[this.t-1] |= x<<sh; sh += k; if(sh >= this.DB) sh -= this.DB; } if(k == 8 && (s[0]&0x80) ! = 0) { this.s = -1; if(sh > 0) this[this.t-1] |= ((1<<(this.DB-sh))-1)<<sh; } this.clamp(); if(mi) BigInteger.ZERO.subTo(this,this); } // (protected) clamp off excess high words function bnpClamp() { var c = this.s&this.DM; while(this.t > 0 && this[this.t-1] == c) --this.t; } // (public) return string representation in given radix function bnToString(b) { if(this.s < 0) return "-"+this.negate().toString(b); var k; if(b == 16) k = 4; else if(b == 8) k = 3; else if(b == 2) k = 1; else if(b == 32) k = 5; else if(b == 4) k = 2; else return this.toRadix(b); var km = (1<<k)-1, d, m = false, r = "", i = this.t; var p = this.DB-(i*this.DB)%k; if(i-- > 0) { if(p < this.DB && (d = this[i]>>p) > 0) { m = true; r = int2char(d); } while(i >= 0) { if(p < k) { d = (this[i]&((1<<p)-1))<<(k-p); d |= this[--i]>>(p+=this.DB-k); } else { d = (this[i]>>(p-=k))&km; if(p <= 0) { p += this.DB; --i; } } if(d > 0) m = true; if(m) r += int2char(d); } } return m? r:"0"; } // (public) -this function bnNegate() { var r = nbi(); BigInteger.ZERO.subTo(this,r); return r; } // (public) |this| function bnAbs() { return (this.s<0)? this.negate():this; } // (public) return + if this > a, - if this < a, 0 if equal function bnCompareTo(a) { var r = this.s-a.s; if(r ! = 0) return r; var i = this.t; r = i-a.t; if(r ! = 0) return r; while(--i >= 0) if((r=this[i]-a[i]) ! = 0) return r; return 0; } // returns bit length of the integer x function nbits(x) { var r = 1, t; if((t=x>>>16) ! = 0) { x = t; r += 16; } if((t=x>>8) ! = 0) { x = t; r += 8; } if((t=x>>4) ! = 0) { x = t; r += 4; } if((t=x>>2) ! = 0) { x = t; r += 2; } if((t=x>>1) ! = 0) { x = t; r += 1; } return r; } // (public) return the number of bits in "this" function bnBitLength() { if(this.t <= 0) return 0; return this.DB*(this.t-1)+nbits(this[this.t-1]^(this.s&this.DM)); } // (protected) r = this << n*DB function bnpDLShiftTo(n,r) { var i; for(i = this.t-1; i >= 0; --i) r[i+n] = this[i]; for(i = n-1; i >= 0; --i) r[i] = 0; r.t = this.t+n; r.s = this.s; } // (protected) r = this >> n*DB function bnpDRShiftTo(n,r) { for(var i = n; i < this.t; ++i) r[i-n] = this[i]; r.t = Math.max(this.t-n,0); r.s = this.s; } // (protected) r = this << n function bnpLShiftTo(n,r) { var bs = n%this.DB; var cbs = this.DB-bs; var bm = (1<<cbs)-1; var ds = Math.floor(n/this.DB), c = (this.s<<bs)&this.DM, i; for(i = this.t-1; i >= 0; --i) { r[i+ds+1] = (this[i]>>cbs)|c; c = (this[i]&bm)<<bs; } for(i = ds-1; i >= 0; --i) r[i] = 0; r[ds] = c; r.t = this.t+ds+1; r.s = this.s; r.clamp(); } // (protected) r = this >> n function bnpRShiftTo(n,r) { r.s = this.s; var ds = Math.floor(n/this.DB); if(ds >= this.t) { r.t = 0; return; } var bs = n%this.DB; var cbs = this.DB-bs; var bm = (1<<bs)-1; r[0] = this[ds]>>bs; for(var i = ds+1; i < this.t; ++i) { r[i-ds-1] |= (this[i]&bm)<<cbs; r[i-ds] = this[i]>>bs; } if(bs > 0) r[this.t-ds-1] |= (this.s&bm)<<cbs; r.t = this.t-ds; r.clamp(); }Copy the code

‘Navigator’ is undefined and willnavigator = thisThe poster

Debug encryption algorithm

Python implementation

Self-write encryption algorithm encryption instance

Log in contract
Suspected point-down debugging
Search encryption algorithm
Implementation of encryption algorithm

function p(e, t) {
var n = (65535 & e) + (65535 & t);
return (e >> 16) + (t >> 16) + (n >> 16) << 16 | 65535 & n
}
function a(e, t, n, o, i, r) {
return p((s = p(p(t, e), p(o, r))) << (a = i) | s >>> 32 - a, n);
var s, a
}
function l(e, t, n, o, i, r, s) {
return a(t & n | ~t & o, e, t, i, r, s)
}
function m(e, t, n, o, i, r, s) {
return a(t & o | n & ~o, e, t, i, r, s)
}
function f(e, t, n, o, i, r, s) {
return a(t ^ n ^ o, e, t, i, r, s)
}
function g(e, t, n, o, i, r, s) {
return a(n ^ (t | ~o), e, t, i, r, s)
}
function c(e, t) {
e[t >> 5] |= 128 << t % 32,
e[14 + (t + 64 >>> 9 << 4)] = t;
var n, o, i, r, s, a = 1732584193,
c = -271733879,
u = -1732584194,
d = 271733878;
for (n = 0; n < e.length; n += 16) a = l(o = a, i = c, r = u, s = d, e[n], 7, -680876936),
d = l(d, a, c, u, e[n + 1], 12, -389564586),
u = l(u, d, a, c, e[n + 2], 17, 606105819),
c = l(c, u, d, a, e[n + 3], 22, -1044525330),
a = l(a, c, u, d, e[n + 4], 7, -176418897),
d = l(d, a, c, u, e[n + 5], 12, 1200080426),
u = l(u, d, a, c, e[n + 6], 17, -1473231341),
c = l(c, u, d, a, e[n + 7], 22, -45705983),
a = l(a, c, u, d, e[n + 8], 7, 1770035416),
d = l(d, a, c, u, e[n + 9], 12, -1958414417),
u = l(u, d, a, c, e[n + 10], 17, -42063),
c = l(c, u, d, a, e[n + 11], 22, -1990404162),
a = l(a, c, u, d, e[n + 12], 7, 1804603682),
d = l(d, a, c, u, e[n + 13], 12, -40341101),
u = l(u, d, a, c, e[n + 14], 17, -1502002290),
a = m(a, c = l(c, u, d, a, e[n + 15], 22, 1236535329), u, d, e[n + 1], 5, -165796510),
d = m(d, a, c, u, e[n + 6], 9, -1069501632),
u = m(u, d, a, c, e[n + 11], 14, 643717713),
c = m(c, u, d, a, e[n], 20, -373897302),
a = m(a, c, u, d, e[n + 5], 5, -701558691),
d = m(d, a, c, u, e[n + 10], 9, 38016083),
u = m(u, d, a, c, e[n + 15], 14, -660478335),
c = m(c, u, d, a, e[n + 4], 20, -405537848),
a = m(a, c, u, d, e[n + 9], 5, 568446438),
d = m(d, a, c, u, e[n + 14], 9, -1019803690),
u = m(u, d, a, c, e[n + 3], 14, -187363961),
c = m(c, u, d, a, e[n + 8], 20, 1163531501),
a = m(a, c, u, d, e[n + 13], 5, -1444681467),
d = m(d, a, c, u, e[n + 2], 9, -51403784),
u = m(u, d, a, c, e[n + 7], 14, 1735328473),
a = f(a, c = m(c, u, d, a, e[n + 12], 20, -1926607734), u, d, e[n + 5], 4, -378558),
d = f(d, a, c, u, e[n + 8], 11, -2022574463),
u = f(u, d, a, c, e[n + 11], 16, 1839030562),
c = f(c, u, d, a, e[n + 14], 23, -35309556),
a = f(a, c, u, d, e[n + 1], 4, -1530992060),
d = f(d, a, c, u, e[n + 4], 11, 1272893353),
u = f(u, d, a, c, e[n + 7], 16, -155497632),
c = f(c, u, d, a, e[n + 10], 23, -1094730640),
a = f(a, c, u, d, e[n + 13], 4, 681279174),
d = f(d, a, c, u, e[n], 11, -358537222),
u = f(u, d, a, c, e[n + 3], 16, -722521979),
c = f(c, u, d, a, e[n + 6], 23, 76029189),
a = f(a, c, u, d, e[n + 9], 4, -640364487),
d = f(d, a, c, u, e[n + 12], 11, -421815835),
u = f(u, d, a, c, e[n + 15], 16, 530742520),
a = g(a, c = f(c, u, d, a, e[n + 2], 23, -995338651), u, d, e[n], 6, -198630844),
d = g(d, a, c, u, e[n + 7], 10, 1126891415),
u = g(u, d, a, c, e[n + 14], 15, -1416354905),
c = g(c, u, d, a, e[n + 5], 21, -57434055),
a = g(a, c, u, d, e[n + 12], 6, 1700485571),
d = g(d, a, c, u, e[n + 3], 10, -1894986606),
u = g(u, d, a, c, e[n + 10], 15, -1051523),
c = g(c, u, d, a, e[n + 1], 21, -2054922799),
a = g(a, c, u, d, e[n + 8], 6, 1873313359),
d = g(d, a, c, u, e[n + 15], 10, -30611744),
u = g(u, d, a, c, e[n + 6], 15, -1560198380),
c = g(c, u, d, a, e[n + 13], 21, 1309151649),
a = g(a, c, u, d, e[n + 4], 6, -145523070),
d = g(d, a, c, u, e[n + 11], 10, -1120210379),
u = g(u, d, a, c, e[n + 2], 15, 718787259),
c = g(c, u, d, a, e[n + 9], 21, -343485551),
a = p(a, o),
c = p(c, i),
u = p(u, r),
d = p(d, s);
return [a, c, u, d]
}
function u(e) {
var t, n = "";
for (t = 0; t < 32 * e.length; t += 8) n += String.fromCharCode(e[t >> 5] >>> t % 32 & 255);
return n
}
function d(e) {
var t, n = [];
for (n[(e.length >> 2) - 1] = void 0, t = 0; t < n.length; t += 1) n[t] = 0;
for (t = 0; t < 8 * e.length; t += 8) n[t >> 5] |= (255 & e.charCodeAt(t / 8)) << t % 32;
return n
}
function o(e) {
var t, n, o = "0123456789abcdef",
i = "";
for (n = 0; n < e.length; n += 1) t = e.charCodeAt(n),
i += o.charAt(t >>> 4 & 15) + o.charAt(15 & t);
return i
}
function i(e) {
return unescape(encodeURIComponent(e))
}
function r(e) {
return u(c(d(t = i(e)), 8 * t.length));
var t
}
function s(e, t) {
return function(e, t) {
var n, o, i = d(e),
r = [],
s = [];
for (r[15] = s[15] = void 0, 16 < i.length && (i = c(i, 8 * e.length)), n = 0; n < 16; n += 1) r[n] = 909522486 ^ i[n],
s[n] = 1549556828 ^ i[n];
return o = c(r.concat(d(t)), 512 + 8 * t.length),
u(c(s.concat(o), 640))
} (i(e), i(t))
}
function getpwd(e, t, n) {
return t ? n ? s(t, e) : o(s(t, e)) : n ? r(e) : o(r(e))
}
Copy the code

Debug encryption algorithm
Python implementation

conclusion

The above is several common front-end encryption algorithm processing

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Examples of common encryption methods

MD5 Encryption instance

RSA Asymmetric key encryption instance

Self-write encryption algorithm encryption instance

conclusion

Examples of common encryption methods

MD5 Encryption instance

RSA Asymmetric key encryption instance

Self-write encryption algorithm encryption instance

conclusion

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