Python3 实现 JS 中 RSA 加密的 NoPadding 模式
前因后果之哗啦啦废话连篇：
这几天本人在 Python 做某网站登陆的时候，发现其登陆时用户名和密码被加密了
F12 仔细看了一下，发现是调用了一个 js 的 rsa 加密库，页面 dom 中有 rsa 公钥
于是乎，用了 3 分钟刷刷的潇洒的写了个 py 脚本，结果对比后傻眼了。。。
web 页面调用 js 库中的加密方式是 nopadding，也就是说，每次加密的结果都一样
而我的 py 脚本每次都不一样！！至于为什么会不一样，以及 padding 的作用请自行百度
于是乎，百度各种 python 库，也没有合适的解决方法
python 库 Crypto 倒是有一个网友给出了方法，但是安装这个库需要安装 Microsoft Visual C++ Build Tools
滚蛋，强行绑架的感觉，还是自己想办法搞定吧。
于是乎...
爆肝研究 RSA 大法
先分析了两个主要 js 文件，Bigint.js 、Barrett.js ，一脸懵逼，一头雾水，不知道再干嘛，仿佛在造一些轮子。。。暂且放过
然后找到了一篇介绍 rsa 加密中 padding 的文章：https://blog.csdn.net/guyongqiangx/article/details/74930951
主要知道了一个事情：
"填充后数据" = "00" + "数据块类型" + "填充字符串" + "00" + "原始数据"
然后又翻看了 python 的 rsa 库源码，其中有一个函数 _pad_for_encryption() ，很可疑，正是在做上述填充数据的事：
此函数位于 python 的 rsa 库 /pkcs1.py 文件中
def _pad_for_encryption(message, target_length):
r"""Pads the message for encryption, returning the padded message.
:return: 00 02 RANDOM_DATA 00 MESSAGE
>>> block = _pad_for_encryption(b'hello', 16)
>>> len(block)
16
>>> block[0:2]
b'\x00\x02'
>>> block[-6:]
b'\x00hello'
"""
max_msglength = target_length - 11
msglength = len(message)
if msglength > max_msglength:
raise OverflowError('%i bytes needed for message, but there is only'
' space for %i' % (msglength, max_msglength))
# Get random padding
padding = b''
padding_length = target_length - msglength - 3
# We remove 0-bytes, so we'll end up with less padding than we've asked for,
# so keep adding data until we're at the correct length.
while len(padding) < padding_length:
needed_bytes = padding_length - len(padding)
# Always read at least 8 bytes more than we need, and trim off the rest
# after removing the 0-bytes. This increases the chance of getting
# enough bytes, especially when needed_bytes is small
new_padding = os.urandom(needed_bytes + 5)
new_padding = new_padding.replace(b'\x00', b'')
padding = padding + new_padding[:needed_bytes]
assert len(padding) == padding_length
return b''.join([b'\x00\x02',
padding,
b'\x00',
message])
重点看 return 的数据，和上面所述的填充方法完全一致。
既然是 nopadding，那就把填充的值全部设置为\x00，填充方式也选\x00，把上述方法关键位置给改掉
完事，重新运行代码，加密后的数据确实不变了，每次都一样，但是和 web 页面中 js 库的还是不一样
突然想到，去看看这个 js 库的官方文档！！
找了又找，终于找到：http://www.ohdave.com/rsa/
介绍中有一个带注释版本 js 文件：http://www.ohdave.com/rsa/RSA.js
里面开头就介绍了 padding 的填充方式：
* Plaintext In * ------------ * * d5 d4 d3 d2 d1 d0 * * * NoPadding * --------- * * 00 00 00 00 00 00 00 00 00 /.../ 00 00 d0 d1 d2 d3 d4 d5
果然有猫腻，这里的实现，是把需要加密的字符串反转，然后其他位全部填充\x00
既然知道了具体的填充方法，那就再改动一下 python 的 rsa 库_pad_for_encryption()函数
果然
加密的结果和 web 中的 js 库加密的结果一样（使用相同的公钥）
最后撤销对 python 的 rsa 库文件修改，导入 rsa 库中的相关函数，封装成自己的函数，直接调用自己函数即可
当然，既然 nopadding 模式的搞定了，也可以搞定其他方式的填充了，但是本人暂时用不到，就没有再继续研究
有兴趣的可以自行研究
至此结束。。
后续
py 文件，js 文件上传 github，需要的自己去看 https://github.com/founddev/evething/tree/master/rsa
=================================================================================
已经转过来
目录结构:
----myrsa.py
----rsa_js(folder)
----------Barrett.js
----------BigInt.js
----------RSA_Stripped.js
myrsa.py
js库rsa加密的nopadding模式python实现
import rsa
m = '86584afb2a8d053ff3bbe054c628521334b40a1e9f0a33308fc95fe8eea227d822a5ea45cfad9bd1c5f89fdb46c5180bfc20f44202fa2d474260e6bca9ffa2d221365f142cd7a022fa8aead20a33f3991447fb085d84b144154f3f728a69166320b3c23745ac464b081add448753f0c8a8c0afe0ef9fbcb7a10710339421c0d7'
e = '10001'
message = '12345678'
dist = '5d6f2b45d89f530e6270c77a2823dbb00bd588a76a9ea872ec8251a4ac32be28102365e9fdde9c1f23f2065ce3baf8bb2a3f84d9a78567752bada6a8e34f0c88d469f2b17f21af50112afd8933d86246bc3a3d8e8e9c441047254999e81c6e1dd9140384e24002a68057328c9123dafe49d74e05afdadba92c4e960883ca777f'
class Encrypt(object):
def __init__(self,e,m):
self.e = e
self.m = m
def encrypt(self,message):
mm = int(self.m, 16)
ee = int(self.e, 16)
rsa_pubkey = rsa.PublicKey(mm, ee)
crypto = self._encrypt(message.encode(), rsa_pubkey)
return crypto.hex()
def _pad_for_encryption(self, message, target_length):
message = message[::-1]
max_msglength = target_length - 11
msglength = len(message)
padding = b''
padding_length = target_length - msglength - 3
for i in range(padding_length):
padding += b'\x00'
return b''.join([b'\x00\x00',padding,b'\x00',message])
def _encrypt(self, message, pub_key):
keylength = rsa.common.byte_size(pub_key.n)
padded = self._pad_for_encryption(message, keylength)
payload = rsa.transform.bytes2int(padded)
encrypted = rsa.core.encrypt_int(payload, pub_key.e, pub_key.n)
block = rsa.transform.int2bytes(encrypted, keylength)
return block
en = Encrypt(e,m)
print(en.encrypt(message))
Barrett.js
js库rsa加密的nopadding模式python实现
// BarrettMu, a class for performing Barrett modular reduction computations in
// JavaScript.
//
// Requires BigInt.js.
//
// Copyright 2004-2005 David Shapiro.
//
// You may use, re-use, abuse, copy, and modify this code to your liking, but
// please keep this header.
//
// Thanks!
//
// Dave Shapiro
// dave@ohdave.com
function BarrettMu(m)
{
this.modulus = biCopy(m);
this.k = biHighIndex(this.modulus) + 1;
var b2k = new BigInt();
b2k.digits[2 * this.k] = 1; // b2k = b^(2k)
this.mu = biDivide(b2k, this.modulus);
this.bkplus1 = new BigInt();
this.bkplus1.digits[this.k + 1] = 1; // bkplus1 = b^(k+1)
this.modulo = BarrettMu_modulo;
this.multiplyMod = BarrettMu_multiplyMod;
this.powMod = BarrettMu_powMod;
}
function BarrettMu_modulo(x)
{
var q1 = biDivideByRadixPower(x, this.k - 1);
var q2 = biMultiply(q1, this.mu);
var q3 = biDivideByRadixPower(q2, this.k + 1);
var r1 = biModuloByRadixPower(x, this.k + 1);
var r2term = biMultiply(q3, this.modulus);
var r2 = biModuloByRadixPower(r2term, this.k + 1);
var r = biSubtract(r1, r2);
if (r.isNeg) {
r = biAdd(r, this.bkplus1);
}
var rgtem = biCompare(r, this.modulus) >= 0;
while (rgtem) {
r = biSubtract(r, this.modulus);
rgtem = biCompare(r, this.modulus) >= 0;
}
return r;
}
function BarrettMu_multiplyMod(x, y)
{
/*
x = this.modulo(x);
y = this.modulo(y);
*/
var xy = biMultiply(x, y);
return this.modulo(xy);
}
function BarrettMu_powMod(x, y)
{
var result = new BigInt();
result.digits[0] = 1;
var a = x;
var k = y;
while (true) {
if ((k.digits[0] & 1) != 0) result = this.multiplyMod(result, a);
k = biShiftRight(k, 1);
if (k.digits[0] == 0 && biHighIndex(k) == 0) break;
a = this.multiplyMod(a, a);
}
return result;
}
BigInt.js
js库rsa加密的nopadding模式python实现
// BigInt, a suite of routines for performing multiple-precision arithmetic in
// JavaScript.
//
// Copyright 1998-2005 David Shapiro.
//
// You may use, re-use, abuse,
// copy, and modify this code to your liking, but please keep this header.
// Thanks!
//
// Dave Shapiro
// dave@ohdave.com
// IMPORTANT THING: Be sure to set maxDigits according to your precision
// needs. Use the setMaxDigits() function to do this. See comments below.
//
// Tweaked by Ian Bunning
// Alterations:
// Fix bug in function biFromHex(s) to allow
// parsing of strings of length != 0 (mod 4)
// Changes made by Dave Shapiro as of 12/30/2004:
//
// The BigInt() constructor doesn't take a string anymore. If you want to
// create a BigInt from a string, use biFromDecimal() for base-10
// representations, biFromHex() for base-16 representations, or
// biFromString() for base-2-to-36 representations.
//
// biFromArray() has been removed. Use biCopy() instead, passing a BigInt
// instead of an array.
//
// The BigInt() constructor now only constructs a zeroed-out array.
// Alternatively, if you pass <true>, it won't construct any array. See the
// biCopy() method for an example of this.
//
// Be sure to set maxDigits depending on your precision needs. The default
// zeroed-out array ZERO_ARRAY is constructed inside the setMaxDigits()
// function. So use this function to set the variable. DON'T JUST SET THE
// VALUE. USE THE FUNCTION.
//
// ZERO_ARRAY exists to hopefully speed up construction of BigInts(). By
// precalculating the zero array, we can just use slice(0) to make copies of
// it. Presumably this calls faster native code, as opposed to setting the
// elements one at a time. I have not done any timing tests to verify this
// claim.
// Max number = 10^16 - 2 = 9999999999999998;
// 2^53 = 9007199254740992;
var biRadixBase = 2;
var biRadixBits = 16;
var bitsPerDigit = biRadixBits;
var biRadix = 1 << 16; // = 2^16 = 65536
var biHalfRadix = biRadix >>> 1;
var biRadixSquared = biRadix * biRadix;
var maxDigitVal = biRadix - 1;
var maxInteger = 9999999999999998;
// maxDigits:
// Change this to accommodate your largest number size. Use setMaxDigits()
// to change it!
//
// In general, if you're working with numbers of size N bits, you'll need 2*N
// bits of storage. Each digit holds 16 bits. So, a 1024-bit key will need
//
// 1024 * 2 / 16 = 128 digits of storage.
//
var maxDigits;
var ZERO_ARRAY;
var bigZero, bigOne;
function setMaxDigits(value) {
maxDigits = value;
ZERO_ARRAY = new Array(maxDigits);
for (var iza = 0; iza < ZERO_ARRAY.length; iza++) ZERO_ARRAY[iza] = 0;
bigZero = new BigInt();
bigOne = new BigInt();
bigOne.digits[0] = 1;
}
setMaxDigits(20);
// The maximum number of digits in base 10 you can convert to an
// integer without JavaScript throwing up on you.
var dpl10 = 15;
// lr10 = 10 ^ dpl10
var lr10 = biFromNumber(1000000000000000);
function BigInt(flag) {
if (typeof flag == "boolean" && flag == true) {
this.digits = null;
}
else {
this.digits = ZERO_ARRAY.slice(0);
}
this.isNeg = false;
}
function biFromDecimal(s) {
var isNeg = s.charAt(0) == '-';
var i = isNeg ? 1 : 0;
var result;
// Skip leading zeros.
while (i < s.length && s.charAt(i) == '0') ++i;
if (i == s.length) {
result = new BigInt();
}
else {
var digitCount = s.length - i;
var fgl = digitCount % dpl10;
if (fgl == 0) fgl = dpl10;
result = biFromNumber(Number(s.substr(i, fgl)));
i += fgl;
while (i < s.length) {
result = biAdd(biMultiply(result, lr10),
biFromNumber(Number(s.substr(i, dpl10))));
i += dpl10;
}
result.isNeg = isNeg;
}
return result;
}
function biCopy(bi) {
var result = new BigInt(true);
result.digits = bi.digits.slice(0);
result.isNeg = bi.isNeg;
return result;
}
function biFromNumber(i) {
var result = new BigInt();
result.isNeg = i < 0;
i = Math.abs(i);
var j = 0;
while (i > 0) {
result.digits[j++] = i & maxDigitVal;
i >>= biRadixBits;
}
return result;
}
function reverseStr(s) {
var result = "";
for (var i = s.length - 1; i > -1; --i) {
result += s.charAt(i);
}
return result;
}
var hexatrigesimalToChar = new Array(
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',
'u', 'v', 'w', 'x', 'y', 'z'
);
function biToString(x, radix)
// 2 <= radix <= 36
{
var b = new BigInt();
b.digits[0] = radix;
var qr = biDivideModulo(x, b);
var result = hexatrigesimalToChar[qr[1].digits[0]];
while (biCompare(qr[0], bigZero) == 1) {
qr = biDivideModulo(qr[0], b);
digit = qr[1].digits[0];
result += hexatrigesimalToChar[qr[1].digits[0]];
}
return (x.isNeg ? "-" : "") + reverseStr(result);
}
function biToDecimal(x) {
var b = new BigInt();
b.digits[0] = 10;
var qr = biDivideModulo(x, b);
var result = String(qr[1].digits[0]);
while (biCompare(qr[0], bigZero) == 1) {
qr = biDivideModulo(qr[0], b);
result += String(qr[1].digits[0]);
}
return (x.isNeg ? "-" : "") + reverseStr(result);
}
var hexToChar = new Array('0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f');
function digitToHex(n) {
var mask = 0xf;
var result = "";
for (i = 0; i < 4; ++i) {
result += hexToChar[n & mask];
n >>>= 4;
}
return reverseStr(result);
}
function biToHex(x) {
var result = "";
var n = biHighIndex(x);
for (var i = biHighIndex(x); i > -1; --i) {
result += digitToHex(x.digits[i]);
}
return result;
}
function charToHex(c) {
var ZERO = 48;
var NINE = ZERO + 9;
var littleA = 97;
var littleZ = littleA + 25;
var bigA = 65;
var bigZ = 65 + 25;
var result;
if (c >= ZERO && c <= NINE) {
result = c - ZERO;
} else if (c >= bigA && c <= bigZ) {
result = 10 + c - bigA;
} else if (c >= littleA && c <= littleZ) {
result = 10 + c - littleA;
} else {
result = 0;
}
return result;
}
function hexToDigit(s) {
var result = 0;
var sl = Math.min(s.length, 4);
for (var i = 0; i < sl; ++i) {
result <<= 4;
result |= charToHex(s.charCodeAt(i))
}
return result;
}
function biFromHex(s) {
var result = new BigInt();
var sl = s.length;
for (var i = sl, j = 0; i > 0; i -= 4, ++j) {
result.digits[j] = hexToDigit(s.substr(Math.max(i - 4, 0), Math.min(i, 4)));
}
return result;
}
function biFromString(s, radix) {
var isNeg = s.charAt(0) == '-';
var istop = isNeg ? 1 : 0;
var result = new BigInt();
var place = new BigInt();
place.digits[0] = 1; // radix^0
for (var i = s.length - 1; i >= istop; i--) {
var c = s.charCodeAt(i);
var digit = charToHex(c);
var biDigit = biMultiplyDigit(place, digit);
result = biAdd(result, biDigit);
place = biMultiplyDigit(place, radix);
}
result.isNeg = isNeg;
return result;
}
function biToBytes(x)
// Returns a string containing raw bytes.
{
var result = "";
for (var i = biHighIndex(x); i > -1; --i) {
result += digitToBytes(x.digits[i]);
}
return result;
}
function digitToBytes(n)
// Convert two-byte digit to string containing both bytes.
{
var c1 = String.fromCharCode(n & 0xff);
n >>>= 8;
var c2 = String.fromCharCode(n & 0xff);
return c2 + c1;
}
function biDump(b) {
return (b.isNeg ? "-" : "") + b.digits.join(" ");
}
function biAdd(x, y) {
var result;
if (x.isNeg != y.isNeg) {
y.isNeg = !y.isNeg;
result = biSubtract(x, y);
y.isNeg = !y.isNeg;
}
else {
result = new BigInt();
var c = 0;
var n;
for (var i = 0; i < x.digits.length; ++i) {
n = x.digits[i] + y.digits[i] + c;
result.digits[i] = n & 0xffff;
c = Number(n >= biRadix);
}
result.isNeg = x.isNeg;
}
return result;
}
function biSubtract(x, y) {
var result;
if (x.isNeg != y.isNeg) {
y.isNeg = !y.isNeg;
result = biAdd(x, y);
y.isNeg = !y.isNeg;
} else {
result = new BigInt();
var n, c;
c = 0;
for (var i = 0; i < x.digits.length; ++i) {
n = x.digits[i] - y.digits[i] + c;
result.digits[i] = n & 0xffff;
// Stupid non-conforming modulus operation.
if (result.digits[i] < 0) result.digits[i] += biRadix;
c = 0 - Number(n < 0);
}
// Fix up the negative sign, if any.
if (c == -1) {
c = 0;
for (var i = 0; i < x.digits.length; ++i) {
n = 0 - result.digits[i] + c;
result.digits[i] = n & 0xffff;
// Stupid non-conforming modulus operation.
if (result.digits[i] < 0) result.digits[i] += biRadix;
c = 0 - Number(n < 0);
}
// Result is opposite sign of arguments.
result.isNeg = !x.isNeg;
} else {
// Result is same sign.
result.isNeg = x.isNeg;
}
}
return result;
}
function biHighIndex(x) {
var result = x.digits.length - 1;
while (result > 0 && x.digits[result] == 0) --result;
return result;
}
function biNumBits(x) {
var n = biHighIndex(x);
var d = x.digits[n];
var m = (n + 1) * bitsPerDigit;
var result;
for (result = m; result > m - bitsPerDigit; --result) {
if ((d & 0x8000) != 0) break;
d <<= 1;
}
return result;
}
function biMultiply(x, y) {
var result = new BigInt();
var c;
var n = biHighIndex(x);
var t = biHighIndex(y);
var u, uv, k;
for (var i = 0; i <= t; ++i) {
c = 0;
k = i;
for (j = 0; j <= n; ++j, ++k) {
uv = result.digits[k] + x.digits[j] * y.digits[i] + c;
result.digits[k] = uv & maxDigitVal;
c = uv >>> biRadixBits;
}
result.digits[i + n + 1] = c;
}
// Someone give me a logical xor, please.
result.isNeg = x.isNeg != y.isNeg;
return result;
}
function biMultiplyDigit(x, y) {
var n, c, uv;
result = new BigInt();
n = biHighIndex(x);
c = 0;
for (var j = 0; j <= n; ++j) {
uv = result.digits[j] + x.digits[j] * y + c;
result.digits[j] = uv & maxDigitVal;
c = uv >>> biRadixBits;
}
result.digits[1 + n] = c;
return result;
}
function arrayCopy(src, srcStart, dest, destStart, n) {
var m = Math.min(srcStart + n, src.length);
for (var i = srcStart, j = destStart; i < m; ++i, ++j) {
dest[j] = src[i];
}
}
var highBitMasks = new Array(0x0000, 0x8000, 0xC000, 0xE000, 0xF000, 0xF800,
0xFC00, 0xFE00, 0xFF00, 0xFF80, 0xFFC0, 0xFFE0,
0xFFF0, 0xFFF8, 0xFFFC, 0xFFFE, 0xFFFF);
function biShiftLeft(x, n) {
var digitCount = Math.floor(n / bitsPerDigit);
var result = new BigInt();
arrayCopy(x.digits, 0, result.digits, digitCount,
result.digits.length - digitCount);
var bits = n % bitsPerDigit;
var rightBits = bitsPerDigit - bits;
for (var i = result.digits.length - 1, i1 = i - 1; i > 0; --i, --i1) {
result.digits[i] = ((result.digits[i] << bits) & maxDigitVal) |
((result.digits[i1] & highBitMasks[bits]) >>>
(rightBits));
}
result.digits[0] = ((result.digits[i] << bits) & maxDigitVal);
result.isNeg = x.isNeg;
return result;
}
var lowBitMasks = new Array(0x0000, 0x0001, 0x0003, 0x0007, 0x000F, 0x001F,
0x003F, 0x007F, 0x00FF, 0x01FF, 0x03FF, 0x07FF,
0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF);
function biShiftRight(x, n) {
var digitCount = Math.floor(n / bitsPerDigit);
var result = new BigInt();
arrayCopy(x.digits, digitCount, result.digits, 0,
x.digits.length - digitCount);
var bits = n % bitsPerDigit;
var leftBits = bitsPerDigit - bits;
for (var i = 0, i1 = i + 1; i < result.digits.length - 1; ++i, ++i1) {
result.digits[i] = (result.digits[i] >>> bits) |
((result.digits[i1] & lowBitMasks[bits]) << leftBits);
}
result.digits[result.digits.length - 1] >>>= bits;
result.isNeg = x.isNeg;
return result;
}
function biMultiplyByRadixPower(x, n) {
var result = new BigInt();
arrayCopy(x.digits, 0, result.digits, n, result.digits.length - n);
return result;
}
function biDivideByRadixPower(x, n) {
var result = new BigInt();
arrayCopy(x.digits, n, result.digits, 0, result.digits.length - n);
return result;
}
function biModuloByRadixPower(x, n) {
var result = new BigInt();
arrayCopy(x.digits, 0, result.digits, 0, n);
return result;
}
function biCompare(x, y) {
if (x.isNeg != y.isNeg) {
return 1 - 2 * Number(x.isNeg);
}
for (var i = x.digits.length - 1; i >= 0; --i) {
if (x.digits[i] != y.digits[i]) {
if (x.isNeg) {
return 1 - 2 * Number(x.digits[i] > y.digits[i]);
} else {
return 1 - 2 * Number(x.digits[i] < y.digits[i]);
}
}
}
return 0;
}
function biDivideModulo(x, y) {
var nb = biNumBits(x);
var tb = biNumBits(y);
var origYIsNeg = y.isNeg;
var q, r;
if (nb < tb) {
// |x| < |y|
if (x.isNeg) {
q = biCopy(bigOne);
q.isNeg = !y.isNeg;
x.isNeg = false;
y.isNeg = false;
r = biSubtract(y, x);
// Restore signs, 'cause they're references.
x.isNeg = true;
y.isNeg = origYIsNeg;
} else {
q = new BigInt();
r = biCopy(x);
}
return new Array(q, r);
}
q = new BigInt();
r = x;
// Normalize Y.
var t = Math.ceil(tb / bitsPerDigit) - 1;
var lambda = 0;
while (y.digits[t] < biHalfRadix) {
y = biShiftLeft(y, 1);
++lambda;
++tb;
t = Math.ceil(tb / bitsPerDigit) - 1;
}
// Shift r over to keep the quotient constant. We'll shift the
// remainder back at the end.
r = biShiftLeft(r, lambda);
nb += lambda; // Update the bit count for x.
var n = Math.ceil(nb / bitsPerDigit) - 1;
var b = biMultiplyByRadixPower(y, n - t);
while (biCompare(r, b) != -1) {
++q.digits[n - t];
r = biSubtract(r, b);
}
for (var i = n; i > t; --i) {
var ri = (i >= r.digits.length) ? 0 : r.digits[i];
var ri1 = (i - 1 >= r.digits.length) ? 0 : r.digits[i - 1];
var ri2 = (i - 2 >= r.digits.length) ? 0 : r.digits[i - 2];
var yt = (t >= y.digits.length) ? 0 : y.digits[t];
var yt1 = (t - 1 >= y.digits.length) ? 0 : y.digits[t - 1];
if (ri == yt) {
q.digits[i - t - 1] = maxDigitVal;
} else {
q.digits[i - t - 1] = Math.floor((ri * biRadix + ri1) / yt);
}
var c1 = q.digits[i - t - 1] * ((yt * biRadix) + yt1);
var c2 = (ri * biRadixSquared) + ((ri1 * biRadix) + ri2);
while (c1 > c2) {
--q.digits[i - t - 1];
c1 = q.digits[i - t - 1] * ((yt * biRadix) | yt1);
c2 = (ri * biRadix * biRadix) + ((ri1 * biRadix) + ri2);
}
b = biMultiplyByRadixPower(y, i - t - 1);
r = biSubtract(r, biMultiplyDigit(b, q.digits[i - t - 1]));
if (r.isNeg) {
r = biAdd(r, b);
--q.digits[i - t - 1];
}
}
r = biShiftRight(r, lambda);
// Fiddle with the signs and stuff to make sure that 0 <= r < y.
q.isNeg = x.isNeg != origYIsNeg;
if (x.isNeg) {
if (origYIsNeg) {
q = biAdd(q, bigOne);
} else {
q = biSubtract(q, bigOne);
}
y = biShiftRight(y, lambda);
r = biSubtract(y, r);
}
// Check for the unbelievably stupid degenerate case of r == -0.
if (r.digits[0] == 0 && biHighIndex(r) == 0) r.isNeg = false;
return new Array(q, r);
}
function biDivide(x, y) {
return biDivideModulo(x, y)[0];
}
function biModulo(x, y) {
return biDivideModulo(x, y)[1];
}
function biMultiplyMod(x, y, m) {
return biModulo(biMultiply(x, y), m);
}
function biPow(x, y) {
var result = bigOne;
var a = x;
while (true) {
if ((y & 1) != 0) result = biMultiply(result, a);
y >>= 1;
if (y == 0) break;
a = biMultiply(a, a);
}
return result;
}
function biPowMod(x, y, m) {
var result = bigOne;
var a = x;
var k = y;
while (true) {
if ((k.digits[0] & 1) != 0) result = biMultiplyMod(result, a, m);
k = biShiftRight(k, 1);
if (k.digits[0] == 0 && biHighIndex(k) == 0) break;
a = biMultiplyMod(a, a, m);
}
return result;
}
RSA_Stripped.js
js库rsa加密的nopadding模式python实现
var RSAAPP = {};
RSAAPP.NoPadding = "NoPadding";
RSAAPP.PKCS1Padding = "PKCS1Padding";
RSAAPP.RawEncoding = "RawEncoding";
RSAAPP.NumericEncoding = "NumericEncoding"
function RSAKeyPair(encryptionExponent, decryptionExponent, modulus, keylen) {
this.e = biFromHex(encryptionExponent);
this.d = biFromHex(decryptionExponent);
this.m = biFromHex(modulus);
if (typeof(keylen) != 'number') {
this.chunkSize = 2 * biHighIndex(this.m);
}
else {
this.chunkSize = keylen / 8;
}
this.radix = 16;
this.barrett = new BarrettMu(this.m);
}
function encryptedString(key, s, pad, encoding) {
var a = new Array();
var sl = s.length;
var i, j, k;
var padtype;
var encodingtype;
var rpad;
var al;
var result = "";
var block;
var crypt;
var text;
if (typeof(pad) == 'string') {
if (pad == RSAAPP.NoPadding) {
padtype = 1;
}
else if (pad == RSAAPP.PKCS1Padding) {
padtype = 2;
}
else {
padtype = 0;
}
}
else {
padtype = 0;
}
if (typeof(encoding) == 'string' && encoding == RSAAPP.RawEncoding) {
encodingtype = 1;
}
else {
encodingtype = 0;
}
if (padtype == 1) {
if (sl > key.chunkSize) {
sl = key.chunkSize;
}
}
else if (padtype == 2) {
if (sl > (key.chunkSize - 11)) {
sl = key.chunkSize - 11;
}
}
i = 0;
if (padtype == 2) {
j = sl - 1;
}
else {
j = key.chunkSize - 1;
}
while (i < sl) {
if (padtype) {
a[j] = s.charCodeAt(i);
}
else {
a[i] = s.charCodeAt(i);
}
i++;
j--;
}
if (padtype == 1) {
i = 0;
}
j = key.chunkSize - (sl % key.chunkSize);
while (j > 0) {
if (padtype == 2) {
rpad = Math.floor(Math.random() * 256);
while (!rpad) {
rpad = Math.floor(Math.random() * 256);
}
a[i] = rpad;
}
else {
a[i] = 0;
}
i++;
j--;
}
if (padtype == 2) {
a[sl] = 0;
a[key.chunkSize - 2] = 2;
a[key.chunkSize - 1] = 0;
}
al = a.length;
for (i = 0; i < al; i += key.chunkSize) {
block = new BigInt();
j = 0;
for (k = i; k < (i + key.chunkSize); ++j) {
block.digits[j] = a[k++];
block.digits[j] += a[k++] << 8;
}
crypt = key.barrett.powMod(block, key.e);
if (encodingtype == 1) {
text = biToBytes(crypt);
}
else {
text = (key.radix == 16) ? biToHex(crypt) : biToString(crypt, key.radix);
}
result += text;
}
return result;
}
function decryptedString(key, c) {
var blocks = c.split(" ");
var b;
var i, j;
var bi;
var result = "";
for (i = 0; i < blocks.length; ++i) {
if (key.radix == 16) {
bi = biFromHex(blocks[i]);
}
else {
bi = biFromString(blocks[i], key.radix);
}
b = key.barrett.powMod(bi, key.d);
for (j = 0; j <= biHighIndex(b); ++j) {
result += String.fromCharCode(b.digits[j] & 255, b.digits[j] >> 8);
}
}
if (result.charCodeAt(result.length - 1) == 0) {
result = result.substring(0, result.length - 1);
}
return (result);
}
